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A HISTORY 



OF THE 



Principle of Sufficient Reason : 



Its Metaphysical and Logical 
Formulations 



431658 



BEING 



A DISSERTATION PRESENTED TO THE PHILOSOPHICAL 

FACULTY OF THE UNIVERSITY OF LEIPZIG 

TO SECURE THE DEGREE OF DOCTOR 






OF PHILOSOPHY 



BY 



WILBUR MARSHALL URBAN 



i«97 






CONTENTS. 

CHAPTER I. 

Pages. 

Introductory : The Problem ; The Development of the 
Logical Consciousness in Connection with the Prin- 
ciple of Sufficient Reason, 1-9 

CHAPTER II. 
Pre-Leibnitzian Thinking, 9-20 

CHAPTER III. 

Origin of the Problem: The Leibnitzians; Metaphysical 

and Logical Motives, 2 °-3 1 ' 

CHAPTER IV. 

Sufficient Reason as the Basal Principle of Meta- 
physics: The Kantians, 3 1—5 1 

CHAPTER V. 

Tm. Struggle between Metaphysical and Logical 

Motives: Herbart and Trendelenburg, 5 2 -6/ 

CHAPTER VI. 

Sufficieni Reason as the Basal Law of Logic: Sigwart, 

Erd m< W\ ndt 68-84 

CONCLI SION. 
l Results 85 <ss 






THE HISTORY OF THE PRINCIPLE OF SUFFICIENT 

REASON: ITS METAPHYSICAL AND 

LOGICAL FORMULATIONS. 

WILBUR URBAN, Ph.D., 

Reader in Philosophy, Princeton University, 

CHAPTER I. 

Introductory. — The Problem. 

The following essay may be looked upon as an attempt to 
show, by means of a historical study of the development of 
the principle of Sufficient Reason, the standpoint occupied 
by the modern German logicians, as contrasted with the 
Epistemologists of the metaphysical schools. As the title 
indicates, the nature of the principle has completely changed 
in the development of post-Leibnitzian thought. In its 
origin, conceived of as extra-logical, as metaphysical and as 
identified with the causal axiom, it has finally been accorded 
the place of basal law of the logical consciousness and only 
secondarily connected with the real relations of causality. 

The extension of the bounds of the logical consciousness, 
involved in this transformation, the critical determination of 
the relation of metaphysical to logical principles resulting 
from such a development are both phenomena characteristic 
of the modern " Erkentniss-theoretische " logic. 

It is the writer's notion that the achievement of these 
characteristic standpoints is in great part the result of reflec- 
tion'upon the nature of this Law of Ground, variously form- 
ulated as metaphysical and logical, and that a conscientious 
study of the history of the principle would throw much light 
upon the growth of our broader view of logic. 



In addition to this the writer was much charmed with the- 
elements of clearness and unity which Schopenhauer, despite 
his many metaphysical sins, was enabled to give to his 
thinking by following the guiding thread of the specific yet 
far-reaching problem of Sufficient Reason. And what is- 
true of Schopenhauer in so great a degree, may be said 
with more or less truth of all the great philosophers since 
Leibnitz. How should we have so clear a notion of Kant's 
chapter upon the " Grundsatze der reinen Verstandes begriffe " 
if he had not gathered them all under the one principle of 
ground ? Without Herbart's " Methodologie," which has 
the problem of ground and consequence as the main object 
of his dialectical interest, the rest of the " Metaphysik ' r 
were scarcely understandable. 

. The conncxio rcrum is the great problem of metaphysics, 
the connexio idearum the last question of logic in its broadest 
sense, and in no way have the mutual relations of the two 
been so subtly elucidated as in the critical study of this basal 
principle of Sufficient Reason. 

Starting then with these two ideas, on the one hand, if 
possible, of showing the fundamental place of the principle 
under consideration, in the philosophical systems of the 
more important Post-Leibnitzians, and secondly of discovering, 
in the development of the law likewise the development of 
the modern concept of logic and its problems, my study has 
produced the following essay. 

A short preliminary chapter upon the Pre-Leibnitzians, 
attempts to show the conditions out ot which Leibnitz's 
quite original formulation of this entirely new principle 
arose. Leibnitz is treated with considerable detail with the 
desire of showing that his formulation discloses the presence 
of two motives, one which tended to formulate the law as a 
Logical principle, the other, the one which finally predomin- 
ated being metaphysical, reduced the problems of the grounds 
of knowledge to a metaphysical determinism. 

The succeeding history of the principle is then conceived 

Khibit three main stag( 



i. The metaphysical formulation of Sufficient Reason, 
from Leibnitz through Kant and Schopenhauer. 

2. A struggle between metaphysical and logical atti- 
tudes iu Herbart and Trendelenburg. 

3. The logical formulation in the modern logicians, Sig- 
wart, Wundt, &c. 

Two questions which may arise, why, on the one hand, 
the study is limited to German thinkers, and secondly, why 
Fichte, Schelling and Hegel are omitted, are answered 
simply : 

By the consideration of the fact that the problem, as limit- 
ed by our study, is exclusively German, the only extra Ger- 
man thinker who has handled the technical problem of Suf- 
ficient Reason being the Kantian, Sir Wm. Hamilton; and 
secondly, the immediate Post-Kantians, especially Hegel, 
represent no new phase of the problem, but rather a return 
to the conditions against which Leibnitz's formulation arose 
as a protest, the pre-critical, pan-logism of the Spinozistic 
type. 

The following study is then concerned with the interplay 
of these two distinct motives, the logical and the metaphys- 
ical, or rather perhaps with the two ways of defining the 
principle of Sufficient Reason. This is the basal law of 
all knowledge, this Law of Ground, and according as it is 
conceived as extra-logical and metaphysical, or on the other 
hand as the most general law of logic, is our whole theory 
of knowledge affected. 

The argument of the succeeding historical study is briefly 
that the origination and first formulation of the principle 
in Leibnitz's thinking, represents a stage of inconsistency 
in which both motives, both attitudes stand in more or less 
contradiction, and that the succeeding movement at first 
manifests a decided trend toward the metaphysical side, to 
be re-placed in more modern thought by the reformation of 
the logical point of view, broadened and changed. 

I. Leibnitz's origination of the principle of Sufficient 
Reason is found to have arisen out of a protest against the 



general trend o-f previous thinking toward a reduction of 
empirical causal relations to logical grounding, as typified in 
the pan-logism of Spinoza. 1 Asa consequence S. R. is con- 
ceived as purely empirical and extra-logicaL 2 Since its 
validity is not grounded in general logical considerations, 
Leibnitz seeks to ground it in his peculiar metaphysical: 
system the Monadologie. The metaphysical causality of the 
monadic development being the ground of empirical happen- 
ing, Sufficient Reason is identified with the Causal Axiom, 
thus rescuing the Causal Axiom from a purely logical treat- 
ment, but setting the current in the direction of a metaphysi- 
cal formulation of the new principle. 3 The logical consequence 
of this identification of causation with S. R., that S. R. be 
conceived as a principle of determination, just as the logical 
norms, Leibnitz did not admit, but insisted that this law was 
only one of sufficient reason instead of determining ground. 4 
At this point Crusius takes up the problem substituting 
" determinateness " for "sufficiency" and distinguishing 
besides the ideal grounds, two distinct kinds of real meta- 
physical grounding, the grounds of will acts and the causes 
of empirical happening. The problem of "determinism," 
in the moral sphere, thus forces the metaphysical side of the 
problem into the foreground. 5 

The advent of the critical philosophy of Kant, repre- 
sents, strange as it may seem, on one side at least, a further 
development of this metaphysical treatment of S. R. He 
maintains the idea of Crusius that the law of ground is a 
principle of determination and not of " sufficiency," and 
accepts the "determination" element in the judgment of 
ground and consequence as a necessity to be metaphysically 
grounded. 6 For the knowledge of this determining ground 
out side of logic a transcendental principle of knowledge 
other than Logical is then necessary. 7 Though denying the 
po isibilif v oi an ontology of the real, he proceeds to ontolo- 

] cf. \\ iS, 19. 5 cf. \ 27. 

«cf. : 8 cf. I 32. 

* \ 22. 4 cf. \ 22. 7 cf. \ 34. 



5 

gize this most fundamental of knowledge principles. It is 
conceived of as extra-logical and ^r^-scendental. 1 Finally 
Schopenhauer defines it as meta-logical and as the transcen- 
dental knot of the Subject-Object relation, which likewise 
marks its most complete divorce from a logical point of view, 
since an Intellectual Intuition of metaphysical relations is 
substituted for the logical thinking of ground and conse- 
quence. 2 

II. What we have been led to call the logical motive for 
Leibnitz's formulation of the new law of knowledge, is ex- 
pressed in this great thinker's attempt to formulate its place 
in relation to logical laws. As we have seen, it was defined 
as extra-logical, in view of the formal and yet metaphysical 
theory of logical necessity against which the new law arose 
as a protest. 3 And yet this very protest indicated a desire 
to extend the narrow bounds of the logical consciousness 
beyond its formal limits, so as to include all knowledge pro- 
cesses. Leibnitz's most general definition of S. R. is at the 
same time the most general definition of the logical con- 
sciousness as conceived to-day. 4 And besides logical neces- 
sity among ideas clear and distinct was conceived to be the 
teleological goal of the confused ideas of which S. R. was 
developed as the empirical law. This inherent possibilitv in 
the Leibnitzian thinking of extending the concepts of logic 
in such a manner as to include Sufficient Reason as a basal 
principle we shall call the logical motive. 

In the Leibnitzian school itself Wolff showed a tendency, 
in contrast to that of Crusius, to include Sufficient Reason 
as a distinct logical principle, side by side with Identity 
and Contradiction. But his attempt to deduce S. R. from 
the other two laws led back to the formalism and ontolog- 
ical way of looking at things against which Leibnitz had 
protested. 5 The critical philosophy of Kant, notwithstand- 
ing the fact that on one side it is but a continuation of the 
metaphysical tradition, nevertheless represents a stage in 

1 cf. §40. *cf. §21. 

2 cf. \ 51. 3 cf. \\ 20, 21. 5 cf. \ 26. 



the development of the modern logical consciousness, and 
the corresponding treatment of S. R. as the basal law of 
that consciousness. 1 Although S. R. is still identified with 
the causal axiom, it is with the causal axiom as a knowledge 
principle, rather than an ontological principle that Kant is 
concerned. In fact the Law of Ground is found only by a 
deduction from the logical categories 2 (causation being 
derived from the hypothetical judgment.) It is because of 
this critical balance of Kant, which sees that S. R. is essen- 
tially a relation of logical ground and consequence, although 
it is transcendental; in other words, because Kant remains 
within his transcendental logic, that Schopenhauer finds 
fault, and it is for this that he substitutes the doctrine of 
Intellectual Intuition. 3 

From Herbart on, the logical motive makes itself strongly 
felt. The idea of Sufficient Reason as having for its goal a 
contradictionless whole of experience and thought, 4 gives it 
the place of a universal logical principle to which the formal 
laws of Identity and Contradiction are subordinated, although 
Herbart is not able to formulate the law without a meta- 
physical basis. But already in his concept of the "widen- 
ed ground," which should include the whole nexus out of 
which the consequence springs lies the germ of a broader 
view ot logic/' Sufficient Reason, the most general term 
for all necessary relations in knowledge, has as its main 
problem the extent of its application to the real, therefore 
its relation to causality, but it is not identified with causa- 
tion. ,; 

Through the intermediate stages of Trendelenburg and 
Drobisch, to the former of whom, the concept of logic 
included the entire phenomenology of the judgment, formal 
and material; 7 while the latter, i hough retaining the concept 
of a purely formal logic, formulates Sufficienl Reason as the 
basal law ol logic/ the modern logic, as represented by 

1 « ' ■ \ 1 1 5 £ 67. 

'— i 6 *7i. 

7 i 78. 
b i 70. 



Wundt, with its recognition of S. R. as basal principle, is 
finally reached. Sufficient Reason is here the general law 
of the interdependence of all acts of thought, to which the 
normative laws of Identity and Contradiction are subordina- 
ted. 1 And the question of its relation to causality is now a 
critical one — that of the relation of the causal axiom to the 
general logical postulate of Grounding. Sigwart, Lotze and 
Wundt show the impossibility of the identification of causa- 
tion and Sufficient Reason, distinguishing between the deter- 
mining ground as logical and the empirical complex or cause 
on the other hand as only sufficient. 2 

The rise of this broader view of logic on account of which 
^Sufficient Reason was again conceived of as purely a princi- 
ple of knowledge — and not a metaphysical law of the real to 
be identified with causality was much aided by a new motive 
which entered into German thought with the advent of 
the Kantian " Kritik." This may be characterized as an 
attempt to get at the phenomenology of the grounding pro- 
cess. Thus, in addition to the " Objective Deduction" of 
the concepts of the Understanding, substance and causality, 
from the logical categories, a "subjective" deduction is 
added which shall show how, from the nature of our mental 
processes, such objective judgments are possible. 3 It is, 
as Kant himself says, something of the nature of an hypo- 
thesis of causes for the given results in judgment. He 
has in mind an immanental Sufficient Reason or logical 
causality working in the processes themselves. 4 This 
immanental logical -causality includes psychological material 
elements, and thus is paved the way for a study of the 
phenomenology of the logical processes and for a broader 
view of the logical consciousness. This genetic point of 
view was already suggested by the Leibnitzian theory of a 
'teleological movement of consciousness from the obscure, 
>confused ideas, that is from psychological sufficiency to the 
^necessity of the logical clearness and distinctness of the 

'§86. »«4i, 42. 

*U 80, 83, 88. *§ 41 and 42. 



8 

eternal ideas, but could not come to complete expression r . 
owing to the metaphysical interpretations put upon it by 
the Monadologie. Herbart, who represents a stage of con- 
flict between the metaphysical and logical formulations of S. 
R., in his conception of the logical ground so widened as to 
include elements not in the conception as amenable to formal 
logic, conceives this widening as brought about by chance 
suggestions, by " Zufalligen Ansichten," thus admitting a 
psychological element into the process of grounding. 1 Al- 
though the logical causality thus suggested is reduced in his 
system to metaphysical terms, yet it is important to recog- 
nize that Sufficient Reason as a principle of knowledge is 
conceived to be an immanental necessity broader than the 
necessity of formal logic. 

Trendelenburg's theory that logic should be extended to 
include the material, psychological as well as the formal ele- 
ments in the judgment, brings the problem of phenomenol- 
ogy to the front. The modal categories of thought, possi- 
bility, reality, and necessity are, after the manner of Kant's 
" subjective deduction," conceived as phenomenological mo- 
ments in the grounding process, in which the formal and 
material elements are united. 2 It is especially Trendelen- 
burg, who, against the psychological doctrine of " Zufall" 
in the grounding processes develops his doctrine of the 
teleological nature of all grounding processes. 3 They are a- 
" wahres Geschehen " under the law of teleological causality, 
the goal of which causality is Knowledge, including Thought 
and Being. The postulate of an immanental logic, function- 
ing in all judgment processes, becomes a permanent element 
in modern Logic, in Sigwart and Erdman. 4 In Wundt, 
finally, the concept of a Logical Causality as the Law ol 
Ground in its primary form, governing the higher appercep- 
tive proi I- set over against the empirical applications 

of this law, the Causal Axiom, in its two expressions physi- 
cal and psychological causality. The teleological necessity. 

M 3 ^ 78. 

77- 4 SS2. 



of our thought processes is the Law of Ground seen in- 
wardly. 1 

In conclusion, we may make our object and method 
clearer by comparing- in a general way the present problem 
with that which Konig sets himself to solve in his extensive 
history of the "Causal Problem." 2 Here, by an exhaustive 
study, covering two volumes, and comprising a detailed 
exposition and criticism, the author seeks to secure valid 
results for the causal concept of to-day. This involves not 
only the complete metaphysics, but explains the psychologi- 
cal and natural science standpoints of the authors under con- 
sideration. The present essay, on the contrary, aims only 
to show that there has been a continuity in reflection upon 
this more general and more formal principle of Sufficient 
Reason ; that, in the changes of attitude toward it, now 
constructing it logically and again metaphysically, and 
secondly in the way in which natural and psychological 
causality have been conceived to be related to it, an instruc- 
tive insight, not blurred by too much data, may be afforded 
into that somewhat difficult province, the border-land 
between Metaphysics and Logic. In view of this limitation 
of the problem, the writer may then hope to be pardoned for 
what may appear from another standpoint an insufficient 
treatment of very deep and thorough thinkers. 

* 
CHAPTER II. 

Pre-Leibnitzian Thought. 

§ i. In order to understand the origin of Sufficient Reason 
as a general unifying term, under which the more particular 
problems of the Science of Knowledge might be put for- 
ward, as well as to secure an insight into the reasons for its 
dominance of German thought from Leibnitz to the present 
day, it is necessary to sketch the general tendencies of pre^ 
Leibnitzian thought. 

X U 91, 9 2 > 

'* Konig, Edward, " Die Entwickelung des Causal-Problems,'" Leipzig, 1888. 



IO 

There are discoverable tendencies toward a unification of 
the problems of knowledge, which, though general, are yet 
so evident as to excuse the anachronism, of referring for the 
sake of conciseness, to expressions of Sufficient Reason 
before its actual formulation in Leibnitz. 

Provisionally, then, it may be said that Greek thinking 
tended to formulate Sufficient Reason in terms of a naive 
real logic of experience. Christian thought, as typified in 
Augustinre, sought it in an introspective determination of the 
conditions of Belief. The Reason of the former was the 
certainty of the external Intuition, corrected by a dialectical 
removal of contradictions; that of the latter the satisfac- 
tion and certainty of the subjective intuition of the self. 

These general norms being once attained, the tendency was 
to give them universal validity. Thus, Aristotle is found 
studying the movements of knowledge and of ps}' , chological 
processes in general under the same categories as external 
happening. Augustine, on the contrary, can understand his- 
torical happening only as the expression of the Divine Will, 
constructed on the analogy of the experiences of his own 
subjective willing self and its necessities. 

§ 2. The Greek formulation of Sufficient Reason 
reached its fullest expression in Aristotle, — his doctrine of 
causation, Lotze calls the first formulation of the Law of 
Ground. But from this doctrine of causation should not be 
separated Aristotle's applied logic and the realistic doctrine 
of concepts which it involves. The two are closely bound 
together and their unity alone affords the basis for a unitary 
formulation. The distinction between formal and applied 
Logic, in the modern sense, according to which, as shall 
appear later. Sufficient Reason is defined as logical, its appli- 
cation- being material, was not yet made. The real con- 
cept, as participating in the idea, lends itself equally well to 
logical forms and causal constructions— on its ideal side to 

logical formal relations, on its real side to causal construc- 
tion. To formulate a general law, therefore, the whole 

sphere ot mediate knowledge, lying between the intuition ol 



perception, "which is for us first" and the intuition of the 
ideas, "which is in itself first" to use Aristotle's terms, all 
lying between these two extremes of the immediately certain, 
requires sufficient grounds for its certainty. 1 These grounds 
may be determined either by the laws of logic, as developed 
by Aristotle, or by his fourfold doctrine of causation. The 
important point is that in either case the concepts dealt 
with are real, as well as rational, and the conclusions either 
of the principles of logic or of the laws of causation are un- 
questioned constructions of the real. No deep-rooted dis- 
tinction is made between the logical and the causal side of 
thought, because the deeper distinctions of the subjective 
and objective had not arisen. The lack of this distinction 
between formal logical thought and concrete real thought is 
characteristic of a unitary metaphysical point of view. 
It is the naive rationalism which, though it may distinguish 
between ideal and real grounds, makes no essential break 
between them. 

§ 3. From the very beginning of Greek thought this naively 
rationalistic attitude toward reality was marked. All 
attempts to solve the problems of Being and, especially, of 
Becoming, which arose to challenge this attitude, were charac- 
terized by the use of concepts which contained already the 
presupposition of their reality. The vote of Anaxagoras, the 
logical principles of Zeno, Identity and Contradiction, the 
number system of the Pythagoreans were not handled as 
principles of knowledge but as directly analysed out of reality. 
And when Plato became convinced of the dualism between 
the material and ideal world, the essential rationalism of 
Greek thought prevented him from taking the step which 
would to modern thought necessarily follow, of distinguish- 
ing between real cause and ideal ground. The ideas are 
made the causes of material things and are called causes, 2 
and even force is ascribed to them by means of which they 
are able to work upon us and make themselves known. 3 

1 Analyt. Post. 7, p. 100, b. 13. 2 Phddo 95, E. 

8 In the Phaedrus, where Plato's doctrine of Ideas first appears, it is confined to 
anoral ideas. 



12 

This brings with it a complete confusion of ideal and real 
grounds. 1 The ideas are both causes and grounds for the 
knowledge of the real of perception, of which, without the 
mediation of the ideas, there is no knowledge but only belief. 2 

For the knowledge of this world of appearance the ideas 
must be taken into service. But they in turn can only be 
known in an intuition out of time. 

§4. In Aristotle there is no material change in the general 
conception of the essential sameness of logical ground and 
real cause. As we have seen, the validity of the causal and 
logical laws alike rests upon the reality of the general con-' 
cept. Thus Schopenhauer has gathered together in his his- 
torical sketch numerous quotations in which a logical pre- 
mise is called cause, aircov being used for every sort of 
ground. 3 Logical thoughts as well as psychological phe- 
nomena are looked upon as a real happening subject to the 
same construction as other external movements. One dif- 
ference may be distinguished however. The ideas as pure 
form, in Plato's sense, are no longer looked upon as causes 
either of perception or of natural phenomena, but Aristotle 
has reached a critical standpoint from which he is able to see 
that only the general concept, as containing ideal and real 
elements in union, may be conceived of causally. 4 Thus 
instead of Plato's simple ideal causation arises Aristotle's 
more complex doctrine of a fourfold causation, of which 
moving and end causes are the more important. The idea 
is cause only in so far as it is natural force and teleological 
end. But although both moving and end cause, are con- 
sidered principles of Sufficient Reason of Becoming, the 
stress is put upon the teleological side. The cause is poten- 

1 This confusion is characteristic of a stage where the postulate of ground is not 

yet recognized, formulated as a basal principle of thought, but only acts unconscious of 

itself. So all the formulations of Plato appear to us, as Schopenhauer says — " wie der 

Stand der (Jnschuld gegen den der Erkentniss des Guten und BOsen." Vierfache 

'.-]>. [9— cf. also Philebui p. 240. 

pluies — Psychologic dei Erkennens % Leipzig, [893. Anhang % Par. 7. 
• " Vierfache Ww Zureichenden Grundes" £ 56. 

' Si,; 



13 

tentiallty of the effect, because the idea of the effect is con- 
sidered to be already in the cause. In order, therefore, 
that a present real might be seen to be the outcome of pre- 
ceding real conditions, into these conditions was read an 
ndea which rationally could be seen to be the dunamis of the 
; present state. 1 

§5. If for the sake of clearness we follow the use of a 
-biological analogy, we may call attention to the extremely 
undifferentiated state of this life-principle of thought — this 
.fundamental motive of Sufficient Reason. In the absence of 
a sense of the difference even between the necessities of 
thought and reality, it is still less to be expected that we 
shall find a strong sense of the difference between the 
necessities in different spheres of reality — or between sub- 
jective sufficiency and objective necessity. In fact, these 
differentiations, in thought as in material development, 
appear only as the result of tedious processes. To the 
first of these differentiations, the source of the distinction 
between subjective and objective necessity, our attention 
must now be turned. 

§ 6. In addition to the naive rationalism of Greek thinking, 
a second ingredient found its way into modern philosophy, a 
force which, though less obtrusive, is perhaps equally to be 
reckoned with — namely, the subjective psychological doc- 
trine of belief of Mediaeval thought, as formulated in 
Augustine. This, as has already been suggested, sought 
the grounds of real judgments in an introspective determi- 
nation of the subjective conditions of belief. And the norm, 
according to which external realities are judged, is the 
certainty of the subjective intuition of the self. Belief, 
which according to Plato and Aristotle lay outside the 
sphere of knowledge, 2 becomes the very presupposition of 
knowledge. Credo ut intelligam is by no means merely a 
theological axiom, but locates the problem of the grounds of 

1 Ueberweg und Heinze, Geschichte der Philosophies 7th Edition, Vol. I, page 203. 
Aristotle Anal. Post, 87, b, 31. 
2 Cf. § 3. 



H 

knowledge in the subjective assent which accompanies all 
judgment. 1 

§7. This subjective assent or belief, which is evidently in 
the first place psychological, is, however, conceived by 
Augustine to be grounded. It is with the nature of this 
grounded sufficiency that we are alone concerned. That 
something appears in consciousness is certain. Our doubt 
can only extend to the nature of that something. 2 

Now, that which is given to us most certainly and really 
is the consciousness of self, not as a metaphysical substance, 
but as a willing, believing, doubting self — even the last ele- 
ment of doubt making the certainty of the self presence more 
absolute, as Descartes likewise argued. The self is the 
source of all assent — and the certainty of the self the norm 
of the certainty in our assent to other realities. 3 Thus he 
argues; reality must be discovered within us to be after- 
ward extended to the external world — for that to which we 
give our subjective assent of the will is, as Augustine with 
insight expresses it, ''our life." "That which later ripens 
into knowledge must first be grasped by faith; w T ho disdains 
faith will never be able to raise himself to knowledge." 4 
Self-certainty is then the norm according to which assent is 
given to the reality of the elements that enter consciousness. 

£ 8. But the important question arises how may this sub- 
jective certainty, arising out of the assent of the will, which 
Augustine believes to be prior to our extension of knowl- 
edge to the external world, be conceived to be valid also for 
external reality. At this point the Will Metaphysics of 
Augustine enters, together with his Theism. The Will of 
God, as ground of the world, made alter the pattern of the 
Eternal Ideas (a neoplatonic element in his system), is the 
source of our will, as part of the world, and therefore works 

1 " /> PraedestinaHone" — sec. C, 2 — " Ipsum credere nihil aliud ist quam cum 
\on enixn omnis qui cogitat, credit, cum ideo cogitent plerique; 
ital omnia, qui credit et credendo, cogitat et cogitando credit." 

* " Contra AccuUm" [II, C, 11. 

• / Vita," 7, xi. 

,M Tt ■ '■ I .. Job. n, 7. 



i5 

upon the finite will, determining our subjective assent or 
disbelief. Thus is our belief in the truths of the external 
world a direct function of our subjective assent. And for 
Augustine there is really no causality except that deducible, 
theologically, from the nature of the Will of God, and no- 
knowledge except that vouchsafed to our subjective belief. 

§ 9. The reason for our treatment of the Augustinian doc- 
trine of assent, is that it is a typical expression of an important 
element of subjective grounding, taken up into later philoso- 
phy, especially the Cartesian. It expresses, too, the exactly 
opposite standpoint from the Aristotelian, in that while the 
reality of the general concept is in the former taken for 
granted, here concrete subjective reality is the starting 
point. They are alike in this, however, that as in the former 
the grounds of logical knowledge and causes in reality are 
not distinguished, because the reality of the general con- 
cepts is the basis of both, so also in Augustine the grounds 
of truth as discovered in assent, just as the grounds of ex- 
ternal reality, are in both cases ultimately to be found in the 
will of God. 

Thus reconstructing Augustine's theory of Sufficient 
Reason in modern terms, it might be said that to him, what- 
ever satisfies the demands of the Will for the real, and is 
taken up by the transcendental belief, without which the 
inner life is impossible, is true. Whatsoever can be shown 
to be grounded in the Will of God is real. In both cases 
the grounds are ultimately the same. 

§ 10. This Formulation of Ratio Sufficients is, at bottom, 
the expression of the whole mediaeval intuition of the world. 
As Dilthey expresses it " Weiter als Augustinus hat kein 
mittelalterlicher Mensch gesehen." What followed was but 
an impossible attempt to graft the Aristotelian rational- 
ism of concepts upon this Will metaphysic — but it remained 
always " fremdes Gut." 

The Realists sought to find concepts which by their very 
definition would include their reality, concepts which thus 
by the mere application of the Aristotelian syllogism, 



i6 

would build a whole system of objective truth; but these 
verv concepts of the religious consciousness were in reality 
but products of the religious belief that Augustine had 
grounded, and were capable of no more scientific proof. 
This tendency reached its culmination in the famous Ansel- 
mian proof of the existence of God. Against this movement 
appeared, from time to time, the Nominalists, who by means 
of the weapons of scepticism, sought to retain the doc- 
trines of belief grounded on the old Augustinian Will meta- 
physic. The final conflict was fought out between Duns 
Scotus and St. Thomas, — of whom the former was Augus- 
tinian and the latter Aristotelian. But already in the 13th 
century men had begun to speak of a " Two Fold Truth," for 
which there should be two entirely different instruments of 
investigation, one for theology and another for secular 
sciences. Thus began to arise among the scientists a mechan- 
ical doctrine of causation, which later in modern philosophy 
should supply the Ratio Sufficiens of Becoming, of existendi, 
which, as we have already seen, failed entirely in the thinking 
of Augustine. 

§ 11. Descartes' theory of grounding represents, as has 
already been suggested, a union of the Aristotelian and 
Augustinian standpoints, a union which from the point of 
view of clear critical thought, it must be admitted, brought 
only confusion. Although to modern critical insight, they 
both, Aristotle and Augustine, represent extremes of objective 
and subjective treatment of the problems of knowledge, yet 
each is thoroughly consistent. With the former logical 
forms and causal relations are equally of the war}) and woof 
of objective reality, a premise is the cause of a conclusion 
and from a given result the necessary cause is thought, not 
discovered. Augustine, on the contrary, with a subjectivity 
as naive as Aristotle's objectivity, reduces knowledge to 
belief or assent which is a function of the ethical will, but 
not content with finding the grounds of knowledge in the 
subjective will, finds it impossible to construe objective cau- 
sation Otherwise than as a function of the divine will. Conse- 



quently all causes with Augustine are at bottom moral 
causes, as witness his doctrine of history. 

§12. The union of these two standpoints in the Car- 
tesian thinking may be expressed as follows ; 

1. Objective Causation is reducible to logical grounding— 
for causation is the term for the interaction of substances and 
their attributes, and the relation of substance and attribute 
is logical. This depends upon the Aristotelian and Scholas- 
tic theory of the real nature of the general concepts called 
metaphysical substances. 

2. But the reality of these general concepts, upon which 
logical grounding and, consequently, objective causation 
rests, is in turn subject to a psychological grounding, after 
the Augustinian fashion. 

For Descartes starts his reflection from the very same 
point of certainty of the self-intuition, as the outcome of 
doubt, which characterized Augustine's thought. From 
the absolute doubt, with which the "Meditations" begin, 
Descartes is led back to certainty of the self — but not by a 
reference to higher logical criteria as in the process of 
knowledge. "Cogito ergo sum," if of the nature of a logical 
syllogism is &petitio principii of a logical law not yet grounded, 
but if of the nature of an intuition (which is undoubtedly the 
right interpretation) has simply the character of subjective 
belief. Descartes now makes use of the self-intuition in a 
way entirely unwarranted, for this subjective belief is made 
the criterion of logical clearness and distinctness. Every- 
thing that comes to consciousness, si clairissement et sidistincte- 
ment, as the self-intuition is valid, says Descartes, ignoring 
the difference between the clearness and distinctness of the 
self-intuition and of logical and real relations, and failing to 
see that the criteria of the latter can only be logical and real 
relations themselves. 

This mode of procedure, when put in practice by Des- 
cartes, discloses a series of real ideas, which become the 
last grounds of knowledge and of the real. In addition to 
the idea of the self or res cogitans as the ground of all phe- 



nomena of consciousness, we intuit the idea of a res extensa,, 
or objective substance with equal necessity, and as equally 
real, and as the ground of both the " most real" idea of God. 

Thus is developed Descartes' doctrine of a hierarchy of 
real concepts, as far as a theory of objective grounding is con- 
cerned, Aristotelian, but itself ultimately grounded in the 
subjective belief of Augustine. 

§13. The consequence of this for his doctrine of Causa- 
tion is important. " The most perfect knowledge," says 
Descartes, " is the knowledge of results out of their causes. 
The highest point of philosophy is therefore to explain things 
on the ground of the knowledge of God as their creator." 
This last sentence is the logical consequence of a position 
which he himself carefully defines in his argument against 
Gassendi. 1 In the cause all the reality of the result either 
formally or immanently (i. e., either the same realities or 
others that are more perfect) must be contained, for there 
can be in the result no more reality than in the cause." All 
causal relations, then, are reducible to logical relations among 
the modi of these most real substances. For because of the 
substantiality of these most real ideas, their logical relations 
must equal real relations. Thus both the Aristotelian and 
Augustinian elements in Descartes lend themselves to a 
theory which excludes empirical causality as such, and the 
concept of causation is reduced to that of logical grounding. 

§14. And since in the actual application of this logical 
causal principle the last criterion must be the clearness and 
distinctness of subjective certainty, the Sufficient Reason of 
Knowledge is in the last analysis subjective.* And now 
enters the peculiar element of the system. As the meta- 
physical ground of this subjective certainty, God the abso- 
lutely real and veracious, is conceived to be the final war- 
rant and Sufficient Reason of its truth. The concept of 

God, however, was itself only discovered as most real 
through this subjective certainty and belief. The ontologi- 

Cal proof o! the divine existence is but the clothing of 

1 " Maiit<iti< nr in Prima /'///A>.u>/>//i<i," III. 



a religious postulate in false logical forms. Between the 
objective logical and causal world, the world of mediate 
grounding, and the world of subjective assent or belief, 
exists a chasm in the Cartesian thought which has not been 
bridged, and which constitutes what has already been 
described as an unassimilated union of the objectivity of 
Aristotle with the subjectivity of Augustine. Not only is 
real causal happening reduced to logical grounding, but the 
latter in turn to subjective sufficiency. 

§15. This break, then, in the very middle of the Car- 
tesian Theory of Knowledge, shows the problem before 
modern philosophy, to be that of the relation of the sub- 
jective and objective sides of Sufficient Reason, of knowl- 
edge and real ground. As we shall see, it had its first 
definite answer in Kant, though by no means a final one. 

We may, in the second place, see in this contradiction 
between psychology and logic, the germs of the two dis- 
tinctly opposite movements that followed : The rationalis- 
tic doctrine of mediated ground is carried out into a com- 
plete identification of causa and ratio by Spinoza, with an 
absolute neglect of the subjective side. 

§ 16. On the other hand, the intermediate sphere of logical 
causation appears to Malebranche an unassimilated term, and 
the subjective satisfaction is brought into immediate rela- 
tion with the objective Will of God, to the exclusion of the 
intermediate sphere of phenomenal ground and consequence. 
The phenomena are simply occasional causes by means of 
which God satisfies the desires of the subject. Thus, he says 
poetically, " Every idea of the human consciousness is a 
prayer of the will which God satisfies with its consequence." 
On the other hand, every idea in my consciousness is the 
immediate product of the Will of God. We need only 
remark that this, in its essence, is but the " Willens i\nsch- 
auung" of the Middle Ages, and that the possibility of such 
a return (logically) from Descartes shows how imperfect was 
his break from a purely religious intuition of the World. 



20 

§17. The second movement of Spinoza is r however, arr 
absolute break, in that it is built upon the rationalistic germ 
in Descartes, which was the Classical element in Christian 
thinking, the one unassimilated element in its World-intu- 
ition. With him the confusion of causa and ratio was com- 
plete. Because the form of the ontological proof is logical 
and, thus, of the nature of the principle of mediate grounding 
as developed by Descartes, he extends the form of Sufficient 
Reason between phenomena and the objective thing in it- 
self without any question whatever, neglecting the sub- 
jective postulate element in the Ontological Proof. Thus 
Spinoza's Pantheism and determinism become, properly, only 
the realization of Descartes' Ontological Proof, and that 
which Descartes took, ideal and subjective as the ground of 
knowledge for the existence of God, (requiring a correspond- 
ing real cause) was, for Spinoza, real. The concept of God 
not only must have its real counterpart, but it is God him- 
self. The whole of philosophy is thus a logical relation of 
concepts — and neither the problem of a real object to which 
they correspond or a subject to whom they are sufficient 
truth, is at all in question. 

Schopenhauer's study and criticism ot Spinoza is a com- 
plete exposition of this confusion, and in default of space for 
further study, we must refer to him. 1 For us only the main 
outlines are of importance. 

CHAPTER III. 
Origin of rut: Principle — The Li ebnitzians. 

I. The outcome of t he nil ire preceding 1 rend of t bought 
was, as w; have seen, to reduce the problem of causation to 
one of 1« >g leal grounding. That grounding, being metaphysi- 
cally con< 1 ived, involved an identification of the ideal ground 

of knowledge with the material relations of cause and effect. 
This essential lack ot distinction between logical and real 
grounds, arose ir<>m tli<- Aristotelian doctrine that real con- 

1 "Vitrfathi Wurulf \ 



21 

cepts are alike the data of logic and causal judgments; it 
was strengthened by Augustine's theory of a hierarchy of 
subjective certainties or reals, in which real and ideal terms 
are contained without distinction and reached its fullest ex- 
pression in Descartes and Spinoza in an absolute confusion 
of the nature of logical and real relations. 

§ 19. Leibnitz's thinking, then, in so far as the postulate of 
Sufficient Reason and its origin, are concerned, arose as a 
protest against this reduction of cau salty to logical ground- 
ing. But it is against logical grounding hypostatized to onto- 
logical validity, rather than against the essentially logical 
nature of the grounding process that he protests. As has 
been pointed out in the introduction, there is still consider- 
able discussion concerning the interpretation to be given to 
this original principle of Leibnitz. He himself defined it as 
applying distinctly to empirical truth, to verite's de fait, in 
contrast to the verites eternites, concerning which he believed 
logical deduction gave complete and absolute truth. To 
appreciate the place of Sufficient Reason in his theory of 
knowledge, it is important to understand the full force of this 
distinction. Without going fully into the metaphysics of 
the Monad, it will suffice for our understanding of his theory 
of knowledge to call attention to his doctrine of the Monad 
as a self-determining developing real, in which the present 
state is always the presupposition and ground of each suc- 
ceeding state so that one knowing the entire present of the 
Monad could tell its past and future. Since, however, the 
inner happenings in the Monad form the basis of all external 
empirical happenings whatsoever it follows that a dynamic 
law of monadic development, must in some sense or under 
some different aspect, become a law of empirical happening. 
The determination of the first sphere must be ground of the 
determination in the second. Now the self conscious Monad 
is the-one in which the principle of Sufficient Reason manifests 
itself as a law of knowledge, and, as a matter of fact in the 
form of a postulate or demand growing out of the very 
nature of this determination. This demand, as expressed in 



22 

the " Principia Pkilosaphia" that all acts of knowledge shall 
have sufficient grounds, that is, in terms of the " Monado- 
logie," that every state of the self conscious Monad must 
be determined, is further expanded to read, "no fact can 
be considered true, no judgment held as true, if a satis- 
factory ground can not be found, on account of which it is 
thus and not otherwise, although these grounds are often 
unknown to us." (Also Fifth Letter to Clarke §125. ) l 

s?20. Thus worded, the principle is undoubted])' logical, 
that is logical 111 the broad sense that it is a universal postu- 
late or principle of all knowledge. As such it must be con- 
ceived equally as the general law governing judgments 
concerning the vcritcs ctcr/iitcs and judgments regarding the 
vcritcs de fait. And this seems to be the only possible con- 
clusion in regard to a principle stated so broadly and gen- 
erally as the Leibnitzian Law. If Sufficient Reason de- 
mands simply that every judgment should have a reason 
sufficient to explain why it is so and not otherwise, this 
should also include the judgments of formal logic, as well as 
mere judgments of empirical fact. It was a logical motive 
in the truest sense which led to the formulation of such a 
general law of all know ledge. Why then did Leibnitz place 
it side by side with the logical principles of Identity and 
Contradiction — as far as validity is concerned, but confine it 
material principle to matters ol fact, to vcritcs de fait? 

§2 1 . I he answer to this question is simple. Side by side 
with the logical motive which led to the formulation of such 
neral principle of knowledge, psychological and meta- 
physical motives equally strong arose which prevented a 
complete and consistent expression of the logical principle. 

I. The distinction between the eternal and empirical 
truth,, inherited from Descartes, rests upon a psychological 
distinction between clear and confused ideas, which Leib- 
nitz connects very closely with his doctrine ol the Monad. 
NOW it is just with the sphere ol the "confused ideas," in- 

" ' e principe est celui du besoin d'une raison suffisante, pour qu'une chose 
m eVe'menl ait lieu." 



23 

eluding the cases (mentioned b} T Leibnitz in the formulation 
already given) where the grounds are not known at all, that 
the new law of Sufficient Reason is to be concerned. Here 
the formal logical laws do not hold, because a ground cannot ^. 
be such logically if it is not known, or even not clear. 
Leibnitz had in mind, then, a principle which shall supplant 
the laws of Identity and Contradiction in a psychological 
sphere where these do not hold. It is clear, then, why 
Leibnitz places the law of Sufficient Reason side by side with 
those of formal logic, without giving the former the place of 
a logical principle. It is in his system of knowledge prin- 
ciples, extra-logical, but merely because the concept of logic 
is narrowed to its formal side. It is to include just those 
unclear confused elements of our knowledge which are not 
amenable to formal logical principles, but which are not- 
withstanding, subject to law. A new light is thrown upon 
the problem when we consider that the dynamic of the 
Monad consists in the raising into clear apperceptive con- 
sciousness of relation just the petites perceptions, the confused 
ideas for which Sufficient Reason is the law. And the goal 
of this development is logical clearness and distinctness, so 
that a continuous movement from the psychological to the 
logical consciousness is the ideal of knowledge. There is no 
doubt that Leibnitz himself grasped the profound import of 
this idea of a teleology in the very heart of knowledge pro- 
cesses, but he failed to draw the necessary conclusion that the 
whole process must be conceived as logical, and the concept 
of logic extended to include it all. He came near to the idea of 
teleological movement in the apperceptive processes, which 
might be seen to be the very heart of Sufficient Reason — and 
thus to the idea of a logical causality in apperception, later 
developed by Wundt, but he remained bound to narrow views 
of the logical consciousness, which excluded this profound 
insight. 

§22. II. Failing, thus, because of a metaphysical psy- 
chology to extend Sufficient Reason to the whole knowledge 
process, formal logical and sub-logical, and thus to achieve 



24 

an early definition of the logical consciousness, which has in 
later times become so important, he falls back upon his meta- 
physics of the Monad, and formulates Sufficient Reason as 
a metaphysical extra-logical principle. It is identified with 
causality. This metaphysical identification of Sufficient 
Reason with the causal axiom marks an important point in 
the development of thought. On the one hand, in that the 
new law, and therefore the causal axiom, are conceived as 
extra-logical, a bar is set to that logical ontologism of Spinoza 
which reduced causal necessity to logical grounding. On 
the other hand, this same interpretation of the law as extra- 
logical demands a new metaphysical grounding of the causal 
axiom, which should show Sufficient Reason to be a prin- 
ciple of determination of the real, as formal logic is of mere 
concepts. This demand Leibnitz did not fully recognize, 
but conceived his principle as one of "sufficiency" rather 
than "determination." With the criticism of Crusius and 
Kant upon the term "sufficient reason," and their substi- 
tution therefore of the idea of "determining ground," the 
metaphysical motive in force in Leibnitz's thought found its. 
logical conclusion. 

,^23. But we have yet to consider the nature and extent 
of the hitter's metaphysical grounding of his new principle. 
The secret of that lies in the doctrine of the Monad. For 
the sphere of the confused and unclear ideas is not only psy- 
chological but also metaphysical in its import; the movement 
from the confused to the logically clear ideas, the basis of 
his theory ot knowledge, is only conceivable as necessary, on 
the basis of the metaphysical necessity of the determination 
of the Monad. And since the internal happening of the 
Monad is I he metaphysical ground of extcnal phenomenal 

relations, the identification of the basal law of that happen- 
ing, causation, with the basal law of the inner movement of 
the Monad, Sufficient Reason, is logically necessary. 

i- While at bottom a metaphysical principle, it is 
easily conceivable from the foregoing how S. R. in Leib- 
nitz may appeal- now as the outcome of a logical motive, and 



25 

again as the result of psychological considerations. It was 1 
natural that the first formulation of a principle so general, 
and yet so capable of exposing the last roots and problems 
of knowledge, should be uncertain in its distinctions. But 
the state in which the problem was left was perhaps one 
most calculated to attract to it the attention of future thought. 
If Sufficient Reason is a new principle of knowledge, of 
validity for a sphere of ideas not amenable to the norms of 
formal logic, what is the relation of formal logic to knowl- 
edge in general? Must not the bounds of the logical con- 
sciousness — that is the consciousness concerned with neces- 
sary relations among ideas — be extended beyond the sphere 
of formal logic? This was the problem which lay inevitably 
in the origin of Leibnitz's principle. 

§25. But again the impetus to new metaphysical formula- 
tions offered by Leibnitz's origination of his new law was 
immense, and sufficient to obscure the preceding problem of 
the possible extension of the concept of the logical conscious- 
ness. For consider that in the place of the belief in the 
ontological validity of the results of purely formal logic, 
which had begun to wane, there was now offered the prob- 
lem (and the apparent means of solving it) of a metaphysical 
determinism other than logical. Thus was inaugurated the 
great problem of the transcendental grounding of experience 
and of its great postulate, the law of Sufficient Reason. 
This involved the Idealistic position of the identification, not 
of the logical ground with the real ground, but of the trans- 
cendental knowledge grounds with real grounds, the identi- 
fication of phenomenal reality with the knowledge of that re- 
ality. This logical consequence, though not carried out to 
the completeness attained by Kant and Schopenhauer, is yet 
clearly enough implied in Leibnitz's thinking. Thus (in the 
Letters to Clarke, §125) the metaphysical universality of the 
law is' clearly taught It is the principle alike of external 
happening and of the inner life of the Monad, and again the 
highest concept of the source of the principle is that of the 
Creator, "in welchem die Macht die die wirkinden Ursachen- 



26 

schafft und die Weisheit welche die Zweck-thatigen ordnet, 
sich vereinigt finden." 

The difference between Leibnitz and his rationalistic pre- 
decessors is this: He, too, postulates an intellectual world 
ground, with the Christian coloring — believing that it must 
be found eventually in the Will of God. He, too, believes 
that the ideal of knowledge is logical necessity expressed in 
the two positive norms, Identity and Contradiction. But 
the problem of Knowledge he finds not so simple, and in 
order to encompass all possible empirical knowledge a third 
principle is necessary, which he formulates in the general 
and negative way that we have seen. It is general in that it 
is a postulate, that <?// things must have a reason and a cause. 
It is negative in that in its empirical application the postulate 
demands, not that our knowledge proceed by identities and 
lack of contradictions in concepts, but by admitting to the body 
of our knowledge only such facts and judgments of facts that 
have a sufficient reason. 1 The validity of that sufficiency 
he further proceeds to gound metaphysically, as we have 
already seen. That he should have confined the postulate 
of Sufficient Reason to empirical truth is not surprising, nor 
that he should have failed to distinguish the logical from the 
metaphysical aspect; that he had insight enough into its 
logical nature to make it coordinate with the long estab- 
lished norms is what stamps him as the originator of a new 
era in philosophical thinking. 

6. Wolff follows Leibnitz with the attempt at a com- 
plete logical expression of Sufficient Reason although it still 
in the sphere of "Ontologie " or metaphysics. In the 
"Vernunftige Gedanken von Gott % der Well und der Seele" 2 we 
are told thai while equally with the principles of Identity 
and Contradiction, that of Sufficienl Reason lies in the 

nature oi men 4 yet " Leibnitz war der erste seine Wichtigkeit 
zu erkennen, dass nehmlich alle veritates contingentes oder 
alle znialligc Wahrheiten aus diesem Satz als ihren ersten 
Quellen fliessen, ja vermOge desselben, die contingentia ihre 

1 < f. also .i limilar negative formulation by Kant, \\ 36, 39. '§30- 



2/ 

* veritatem determinatem ' haben, vermoge dessen sie ein 
unendlicher Verstand vorher wissen konnte." 

But to the rationalistic mind of Wolff it appeared that if 
"ein unendlicher Verstand" knew these verities beforehand, 
they must be of the nature of logical relations. So that the 
attempt is made to secure the place of Sufficient Reason as a 
logical law, and this, by means of deduction from the law of 
Contradiction. This occurs in "Ontologia" (§§66-70.) A 
thing has either a Sufficient Reason or it has not. In the 
last case it must be granted that there is something which 
has nothing for its ground. But out of nothing can something 
never be known. Baumgarten repeats the same proof in 
Metaphysics § 20. The petitio principii, as well as the confu- 
sion of real and knowledge ground, is evident, and it is upon 
the failure of this proof that Crusius (as we shall see) takes his 
stand for his own point of view. The meaning of this attempt 
to prove logically what Leibnitz had considered in the light 
of a postulate is evidently nothing else than a falling back 
into the rationalism against which the new law had risen as a 
protest. What had been with Leibnitz a postulate of the 
necessary Znsammenhang of the world in the broadest sense, 
and of our ability to understand the same, becomes with 
Wolff a claim for the logical determinism of the things which 
make up the world of contingency. 

To be sure Wolff had distinguished between four prin- 
ciples of Sufficient Reason 1 — cognoscendi, the logical deduc- 
tion of conclusions from premises ; fiendi, from which 
grounds we discover the reality of a thing ; essendi, from 
which the possibility of a thing is seen (relation in space and 
time) ; agendi, in the ground of which w^e see the necessity 
of an act. But with all his important distinctions which 
later figure so materially in the history of the principle, he 
never left the rationalism which, belonged to his intuition of 
the world, for in the last analysis the grounds are always 
determined logically, 2 and grow out of the Scholastic 
definition of the " thing, " as made up of logical characteristics. 

1 Ontologia, § 866. s Ontologia, § 951. 



28 

§27. The studv of Sufficient Reason in the " Entwurf der 
notwendigen Vernunft—Wahrkeiten" 1753, by Crusius is of 
the nature of a weak protest against the Wolffian point of 
view. 1 Wolff had defined philosophy as the science of the 
possible, thus making its criteria purely logical, all that could 
be thought without contradiction being of course possible.. 
This covered his whole view of Sufficient Reason. Crusius 
protested against this by defining Philosophy as the Science 
of the Real. 

A ground to be Sufficient Reason shall not suffice merely 
if it involves no contradiction, but it must so show the rela- 
tion as to make it evident that with the ground the conse- 
quence is necessarily given. How does it affect reality, if the 
opposite can be thought? The existence of the opposite cannot 
be thought of, if the existence is once known to be a real 
fact. 2 Thus the distinction made by Wolff between the abso- 
lute necessity of thought and hypothetical necessity which is 
found in the law of ground in contingent reals is false, and 
arises out of the subjective relation thereto. 3 All necessity 
is absolute, but not all logical and capable of being expressed 
in terms of knowledge. This point is weighty, for his two 
great contributions to the problem are: 

a. His clear distinction between the different spheres of 
the functioning of Sufficient Reason, especially between the 
real and ideal grounds, and: 

b. His especial study of the problem of the ground in the 
sphere of the Will. 

In regard to the first, he complains of the changeable 
meaning applied to the term ground, and especially the fail- 
ure to keep separate the ideal ground of knowledge and the 
real ground, a distinction only suggested by Wolff and not 
carefully adhered to. "Hierdurch (Vermischung) wird 
nichl mir die Aufmerksamkeil auf das wahre Wesen dersel- 
ben verhindert, sondern auch zu der Obereilung Gelegen- 

■ nii.'uiiis — " Dit VernunftUhre )£i2o — also stands for a separation of the meta- 

il application from its application as a logical principle. 

1 Dusertatio Philosophii dt Usu et Limitibus Principii RationU DeUrminamu 

lips. 

l En ■ Not. Wahr. — VIII. Cf. also Kant $39. 



2 9 

heit gegeben, vermoge welcher man annimt dass alle wahr- 
haft zureichende Realgriinde auch zugleich zureichende 
Erkentniss-griinde apriori, sein miissten." l This simply means 
that as far as the Principle of Sufficient Reason is to be ap- 
plied to the real, one can only say a necessary "Zusatnmen- 
Jiang" exists,' according to laws, but in no way does the 
rationalist's postulate follow that their relations may be 
known as logically expressed. It is not a problem of the 
knowledge-ground of the rational possibility of a thing, but 
a postulate of real and necessary relations among things. 

§28. Having thus separated the knowledge or logical 
problem from that of real grounds, he next divides the 
sphere of the latter into two great main divisions, the moral 
and physical real. This, it must be remembered, rose out 
of his moral and religious problem of the freedom of the 
will. In the physical sphere we have two aspects of the real 
ground ; first, the real ground as cause, to explain the prob- 
lem of becoming; and secondly, the real ground as possi- 
bility, in which, like Wolff, he brings to light the space and 
time conditions of empirical judgments, as the conditions of 
the possibility of the real or the "law of ground" of being. 
This was later developed into the Kantian modal category of 
the Possible, the criteria of which are formal. His schemat- 
ism is, so to speak, the setting of the great problem of 
Sufficient Reason which later occupied the minds of Kant 
and Schopenhauer. It may be expressed somewhat as fol- 
lows (De usu, etc., §§35, 36): 

Ground. 



Moral. Physical. 

Real. Knowledge. 



Being-'Cause. Possibility. Apriori. Aposteriori. 

Space and Time. Experience. 

Being. 

1 ■« Eniwurfder Not. Wahr." Chap. 3, § 38. 



30 

§29'. The problem of Sufficient Reason in the sphere of 
Morals or of the Will, is his chief question, and is kept care- 
fully distinct from the physical sphere. But here again 
must be distinguished carefully between the ideal and real 
ground, for we are tempted to consider the idea which we 
call motive, (the idea which is the ground of our being con- 
scious of a will act,) the real cause or ground of that act. 
This is false, for it is foolish to ask for grounds of an act of 
will, for it is simply the nature of will to act as it wills. 
Thus he champions the doctrine of Augustine and Scotus 
that the Will is independent of the " Vorstellungen," not, 
however, indeterminism, for the law of ground lies in the 
Will itself. To ask for its ground in an idea is to confuse 
knowledge and real grounds, for will is real and force. The 
proof of this position we need not give, for it rests upon cer- 
tain errors concerning the definition and relation of the ideas 
of substance and force, and an application of the same to a 
metaphysic of the will in an unjustifiable manner. Sufficient 
for our historical study is it to notice that for the Will, as 
well as for simple Being, is postulated a peculiar law of 
ground which dare not be identified either with causality or 
Ideal ground. 1 

^30. In summing up the Leibnitz-Wolffian movement, we 
may describe it as having three moments: 

(a.) Leibnitz propounds the Principle of Sufficient Reason 
as a postulate of empirical knowledge, extends it in some of 
his formulations to a general logical principle — thus extend- 
ing potentially the sphere of logic beyond the bounds of the 
formal. Not being able to achieve the full formulation of his 
logical motive, he finally secures universality for his new 
principle by yielding to the metaphysical demand which 
identified it with the universal causal determination, devel- 
oped in his System, grounding it on his Monadologie. 

Wolfl attempts to restore the principle to the place of 
a logical law, but through his limited notion of logic and the 

ipt to deduce Sufficient Reason from the principles of 

1 c f. Konig— -" un Us Causal Problems " Chap, on Crasius. 



3i 

Identity and Contradiction, he falls back into Pre-Leibnitz- 
ian Rationalism, (c.) Crusius, in protest against Wolff's 
Rationalism, excludes the law entirely from logic, and de- 
velops the metaphysical motive of Leibnitz still further. 

CHAPTER IV. 

The Kantians. Sufficient Reason as the Basal Law 
of Metaphysics. 

§31. As has been already suggested in the introductory 
chapter, the metaphysical motive in Leibnitz's formulation of 
Sufficient Reason which sought to ground the validity of the 
principle in extra-logical considerations and which was car- 
ried out in Crusius' construction of the law as a principle of 
metaphysical determination rather than of " sufficiency " for 
knowledge, finds its continuation in Kant and Schopenhauer. 
The characteristic of this entire metaphysical movement 
was already prominent in Crusius. Besides the distinction 
between ideal and real grounds, there is a further differentia- 
tion of different classes of real grounds, namely, a) those of 
the Sufficient Reason of Being as afforded by the relations 
of space and time, b) of Sufficient Reason of Becoming, in the 
relations of Causality, c) the grounds of Will acts. This meta- 
physical differentiation of real grounds into three distinct 
classes, becomes prominent, because the essentially unitary 
and logical nature of the l^aw sinks out of sight. 

This unitary^ nature of the Law as a knowledge postu- 
late both Kant and Schopenhauer seek to restore, the former 
by what, following Schopenhauer, we may call Transcen- 
dental Logic, the latter by his doctrine of the Intellectual 
Intuition, both of which are in their essence metaphysical 
principles. 

§ 32*. Kant. Kant may be said to have had as the problem 
of his entire thinking, the nature of philosophical grounds. 
For his starting point was given him by the Leibnitzian 
school, and in the particular problems of Crusius. In the 



32 

"Nova Dilucidatio" (or fully given, " Principium primoriun 
cognitionis metaphysieae nova dilucidatio") 1755 (Kant's Habil- 
itation's Schrift), beside the laws of Identity and Contradic- 
tion is considered the " Satz vom Grunde." 

With Crusius Kant agrees that the term sufficient 
ground (" zureichender ") is weak and chooses ''determin- 
ing " (" bestimmender ") instead. Moreover, he is unsatisfied 
with the definition of Wolff, that the ground is that " durch 
das voraus mehr sei als nicht sei." It explains nothing for 
" voraus\" means simply " aus welchem grund." 1 Thus if 
the only determining ground is that its opposite can not be 
thought, this is only ideal or " uachher bestimmenden Grund" 
and not li vorher bestimmenden." It answers the question of 
the "quod" and not of the "warum" On the basis of this 
distinction between li vorher" or " antecedenter" ground and 
lt nachher" or " consequenter" he insists upon an absolute 
determinism for the former or real ground and justifies this 
thorough-going determinism against the attacks of Crusius, 
who complained that it made impossible the freedom of the 
will. Upon the basis of distinction of real and ideal ground, 
Crusius had maintained that to consider an idea, cause or 
ground of an act of will is to confuse real and ideal grounds. 
This " idea" (Vorstellung) is the Sufficient Reason, as far as 
the knowledge of the act is concerned, but it cannot be said 
that it is determining for the individual Will itself. Will 
contains a law of ground, but a law of its own, for "durch 
das blosse Sctxen dcr Willens Thatigheit alle entgegen- 
tzten Bestimmungen ausgeschlossen warden ; folglich 
isl ein vorher bestimmenden Grund nicht erforderlich." 2 

Kani answers with a keen psychological analysis of the 
Will and its functions, showing that there is a distinction 
een the impulse or desire which is the determining 
ground of the will act and our idea of the same which we use 
i ideal term of the knowledge of will acts. Thus partic- 
ular impulses and desires are the motives or grounds of the 
decisions of the Will, although they are to be included in the 

1 .' "/;• '88 199-203. 



33 

Will itself, and so the postulate of the Law of Ground is ful- 
filled, which demands that every event shall have its Suffi- 
cient Reason or determining ground. 

§33. Kant's next step is in the direction of a closer study 
of the Law of Ground in things — the principle of causation. 
In 1763 appeared the paper entitled "Versuch den Begriff 
der negativen Grossen in die Welt— We is he it hinein zu fiigen" 
in which is to be seen the working of the second force 
brought to bear upon Kant, namely, the Humian criticism. 
Wolff had taken the empirical postulate of Leibnitz and 
given it such a logical turn that all its applications were 
made through the logical principles of Identity and Contra- 
diction, to the latter of which he had tried to make it 
subordinate. Kant sees that in the sphere of the real these 
principles are not applicable. For in actual nature a nega- 
tive force in relation to a positive (and in fact, positive and 
negative functions in general) do not constitute a contradic- 
tion. Though both positive in their nature, they do not 
annul each other as in logic. Thus Wolff in the " Vernunf- 
tige Gedanken" had taken the figure of Archimedes' Scales as 
an intuitive proof of contradiction and Sufficient Reason in 
relation to each other. An exact balance is an intuitive 
contradiction of positive and negative. Now, if one side 
sinks, the contradiction is destroyed and there must be a 
ground why that side has sunk rather than not. Taking 
this same figure of the scales, Kant shows that no logical 
analogy exists, and that one cannot speak of the two sides 
being in contradiction, but rather are both to be considered 
causes in producing an entirely different condition, namely, 
the new state of the balance of the scales. Thus, likewise 
in the sphere of morals, plus-crime and minus-crime do not 
equal zero, nor do pain plus pleasure equal zero, but pro- 
duce an entirely new mental state. He concludes, there- 
fore, that the problem of causation or of real ground lies 
entirely outside the sphere of formal logic. 

§34. It is, however, in the "Grunds'atze des reinen 
Verstandes," that most clearly written chapter of the entire 



34 

Kritik, that we have at the same time the full expression 
of Kant's doctrine of Sufficient Reason and the source of 
Schopenhauer's formulation, with which we shall later be con- 
cerned. After considering the law of Contradiction as the 
supreme principle of analytical judgments, Kant asks the 
question : What is the supreme principle of synthetic judg- 
ments? To this the answer is: the Law of Ground. 1 That 
Kant thus identifies the Law of Ground, the principle of 
empirical judgments, with a synthetic function of mind 
rather than with the analytic procedure of logic, is in har- 
mony with the metaphysical motive of Leibnitz, which 
sought an extra-logical validity for the principle of Sufficient 
Reason. In further asking the question, how synthetic 
judgments a priori, without logical grounds, are possible 
Kant is obeying the logic of the motive and seeking a meta- 
physical source for the validity of the extra-logical law. 
The ontologizing of this fundamental law is the Transcen- 
dental Logic of the Kantian Kritik. 

§35. The general Law of Ground Kant formulates as fol- 
lows: 2 " Ein jeder Gegenstand steht unter den notwendi- 
gen Bedingungen der synthetischen Manigfaltigkeit der 
Anschauung in einer moglichen Erfahrung." That experi- 
ence be possible, it is necessary that in the complexes which 
make it up, necessary and universal conditions or laws of 
ground exist, by which each element may be held in its 
proper place in the whole. What then are the particular 
principles in which the general law expresses itself ? They 
are, according to Kant, four: 

1 Kritik der rHnen Vemunft % (Reclam), p. 202, 17S1 Kdition. Kanf closes the 

chapter on the " Grundsatze " with these significant words : " In Ermangelung dieser 

(which has just preceded — and which we shall give below) " und bei dem 

Wahne, synthetic \\<j S&tze, welcbe tier ErfahrungSgebrauch des Yerstandes als seine 

I'rincipien empfiHilt, dogmatisch beweisen zu wollen, Est es denn gescheben, dass von 

dem Satze des zureichenden Grundes, so oft, aber immer vergeblich ein Beweis ist 

en. An die beiden Qbrigen Analogien hat niemand gedacht (Gemein- 

alit&t des Werdens) . . . weiJ der Leitfaden der Categorien 

des Verstandes, sowohl in Begriffen als Grundsatzen, 

ind merklich machen Icann." 

'Reclam Edition (1781), p. 155. 



35 

I. Axiome der Anschauung, 
II. Anticipationen der Wahrnehmung, 

III. Analogien der Erfahrung, and 

IV. Postulate des empirischen Denkens iiberhaupt. That 
which Kant states in his general formulation — that the 
condition of any experience whatsoever is a supersensuous 
transcendental relativity of all the phenomena of experience, 
a general law of ground and consequence throughout all 
mental content, he proceeds to develop in the particular 
spheres of phenomena. The axioms of the Intuition de- 
mand that relations of space and time, transcendental and 
extra-logical, be present, if we are to have empirical knowl- 
edge or experience at all. The analogies of experience, of 
which the principal cases are the Causal Axiom and the con- 
cept of Substance, afford the transcendental grounds for 
empirical judgments of relations. Causality is the typical 
expression of the law of ground among phenomena and 
changes the intuition of temporal succession into a synthetic 
judgment of the Understanding because by reason of it we 
are by analogy enabled to say a priori that if a certain rela- 
tion of ground and consequence has appeared in experience, 
when the cause again appears it will, under the same condi- 
tions, produce the same effect. 

§36. The law of ground, than, according to the Kantian 
definition, embraces all principles of relativity, universal and 
necessary, which underlie our empirical judgments, and make 
them valid. This validity, which, as we have seen, like 
Leibnitz, he conceives to be extra-logical, is established first 
in a negative way, in that without these transcendental 
principles of relativity, empirical knowledge is impossible. 
It rests upon the postulate of the necessary unity of apper- 
ception in consciousness, which presupposes unity of expe- 
rience to all possible empirical consciousness at any time. 
Thus we have the Law of Ground in causation as a sine qua 
non of a unity of experience, or of the subject-object relation 
in general. 1 This is what Schopenhauer means when he says: 

1 Reclam, p. 172, Part II. 



36 

"experience is through and through causality." It (causation) 
objectifies subjective ideas, renders possible the representa- 
tion of objects, it assigns to each phenomenon, as a conse- 
quence, a determined place according to the Law of Ground, 
in what would otherwise be a merely psychological flow of 
ideas. It renders unified experience possible. The apparent 
petitio principii 1 involved in the claim of the universal validity 
of causality for all experience, because it alone makes expe- 
rience possible, disappears when we reflect that experience 
in the two cases is different. It (causation) is universally 
valid for all particular experiences. It is, however, the con- 
dition of experience in general, transcendental experience. 

$37. In addition to the negative argument, that without 
these transcendental principles of necessary relativity empir- 
ical knowledge is impossible, Kant seeks a more positive 
grounding of the necessary relations of phenomenal reality. 
The question, how are synthetic judgments a priori possible is 
answered by the Objective Deduction of the categories, 
which we have called the Transcendental Logic. Relations 
of space and time, which Kant describes under the general 
terms of Gemei?ischaft des Seins, relations of causality, or 
the Caiisalitcit des Werdens, are the true principles of Sufficient 
Reason of reality. Upon these mathematical and causal 
judgments rest. But these, Kant complains, had remained 
undiscovered, because his predecessors had sought to prove 
the validity of the Law of Ground by subsuming it under the 
principles of formal analytical logic. This was especially 
true in the case of Wolff. It did not occur to them to fol- 
low the guiding thread of the categories which govern our 
synthetic judgments, and which point to transcendental roots. 

The manner in which Kant connects all the empirical 
principles developed in the Grundsatze with the Aristotelian 
categories oi Logical relation — the criticism which this forced 
architectonic lias brought upon him need not detain us here. 
We need only consider the idea which dominated it and its 
application to the two empirical expressions of the Law of 
Ground developed above. 

1 "• • . 23. 



37 

¥ 

§ 38. The principles of necessary relativity in space and 
time which are expressed as community of Being (Gemein- 
schaft des Seins) and causality, are deduced from the two im- 
portant categories of reality and necessity, the categorical 
and the hypothetical judgments. At first sight, it would 
seem that the Law of Ground is recognized as a formal logical 
principle, but in reality this cannot be said to be true. The 
truer view is that these logical forms are the conceptual 
expression of transcendental principles which govern the 
empirical judgments of space, time, and causal relations. 
By following them as a guiding thread we may reach the 
transcendental conditions of knowledge ; they themselves are 
only conceptual signs. In other words it is in their meta- 
physical significance that they constitute the Law of Ground. 
This is Kant's Transcendental Logic. For the hypothetical 
judgment, as a formal relation of concepts, is an analytical 
procedure, says Kant, as a transcendental logic of experience, 
it is synthetic. This distinction Kant brings out clearly in 
a later essay " Ueber die Fortschritte in der Metaphysik 
seit Leibnitz und Wolff." 1 The one great advance he insists 
lies in the fact that the Law of Ground has become entirely 
metaphysical and has ceased to be subsumed under the logical 
laws. 

§ 39. Still more clearly is its relation to logic stated in 
the reply to Eberhardt's criticism of his " Reine Vemunft" % 
where he maintains that the purely logical law, " Ein jeder 
Satz muss einen Grund haben," is clearly subordinate to 
"Contradiction." The Sufficient Reason whose principles 
we have studied is entirely outside the norms of logic, is the 
Sufficient Reason of empirical reality — and as such meta- 
physical in its essence. In thus developing a transcenden- 
tal Law of Ground for empirical reality, of the same validity 
as the logical norms for the sphere of pure concepts, that 
has been found for which Leibnitz in vain sought — an expla- 
nation of the necessity of empirical knowledge. 

1 Complete Works, Hartenstein Edition, Vol. VIII., p. 538. 

2 Hartenstein, C. W. VI., p. 10, "Ueber eine neue Entdeckung nach der atte 
Vernunft Kritik entbehrlich gemacht werden sol/.' 1 



38 

The distinction between the logical postulate of Ground 
and Consequence, and the metalogical principles of trans- 
scendental validity which give necessity to phenomenal rela- 
tions is the cardinal point of Kant's thinking from the stand- 
point of the study in hand, and remains, as we shall see, an 
unsolved dualism in his theory of knowledge. 

Having confined the logical Law of Ground to the formu- 
lation, "Ein jeder Satz muss einen Grund haben," Kant 
finds the corresponding postulate of the transcendental logic 
expressed in what he calls the chief postulate of empirical 
thought in general, "In mundo non datur hiatus, non datur 
sa/tus, non datur casus, non datur fatum." This postulate 
is the underlying condition of all experience, and expresses 
the necessity inherent in the forms of space, time and caus- 
ality already considered. 1 

£ 40. The metaphysical tendency in Leibnitz's formulation 
of the law is thus carried a step further. The impulse which 
led Kant in his earlv essay to substitute, in agreement with 
Crusius, "determining grounds" for "sufficient reason," 
and upon the study of Hume, to separate absolutely the 
necessity of formal logic from that of empirical knowledge, 
leads him to a metaphysical construction of all empirical 
determination and to ground this determinism, not in an 
ontology of the real, such as the Leibnitzian Monadism, but 
in an ontology of our knowledge processes, which has been 
called the Transcendental Logic. 

We may therefore formulate Kant's doctrine of Sufficient 
Reason as follows: The Law of Ground is the fundamental 
postulate of empirical knowledge, "das oberste Principium 
aller synthetischen rrtheile," in thai it demands that every 
phenomenal element shall have a necessary phenomenal 
ground. The empirical expressions of that law are the 
necessary relations of space, time and eausalitv. Since, 

1 As a result of the whole study we find these words <>f Kant, as the rule of 

pineal investigation : " In der empirischen Synthesis nichts zuzulassen was dera 

Verstande und dem continuirlichen Zusammenhange aller Enscheinungen d. i. der 

than lednnte. Denn er ist es alleinworin die Einheit der 

inning in der .ill.- Wahrnehnuin^en ihre stelle haben mussen, tndglich wird." 



39 

however, the Law of Ground is merely a phenomenal prin- 
ciple, necessity only a subjective postulate, empirical reality 
and the knowledge of that reality fall together, and the law 
of ground is likewise a principle of real necessity — in other 
words, a metaphysical principle metaphysically grounded as 
we have seen. 

It is however, and this is an important proviso, only by 
following the " Leitfaden " of the logical categories that the 
necessary empirical relations are discovered. Thus, while 
the Law of Ground is not confined to the formal logical 
expression of the postulate " ein jeder Satz muss einen Gund 
haben," it is nevertheless logical in its essence, in that in all 
the phenomenal manifestations of the principle, the axioms 
of the spacial and causal world, logical dependence is the 
transcendental concept which underlies them. 

§41. From this two important results for historical con- 
sideration follow : 

1. A distinct movement toward a development of a 
broader view of the logical consciousness is discernable. 
Though Kant defined the Law of Ground or Sufficient 
Reason as extra-logical and transcendental, it was only such 
in so far as by logical the formal logic of concepts was meant. 
That he recognized the logical kernel in the Causal axiom, 
and even tried to find it in spatial and temporal relations 
of coexistence, indicates his appreciation of some of the 
problems of logic in its broader sense. Thus by means of a 
subjective deduction of the categories which should be of 
the nature of a " psychologische Erganzung" to the objec- 
tive logical deduction, and which should show how "das 
Vermogen zu denken selbst moglich Sei was gleichsam die 
Aufsuchung der Ursache zu einer gegebenen Wirkung sei," 
rand " insofern etwas einer Hypothese ahnliches an sich 
.habe," 1 Kant sought to show, by means of the psychological 
iphenomenology of judgment, how the Law of Ground was 
.equally the basal law of the intuitional and conceptional ele- 

1 Kritik der R. V., introduction to first edition. Cf. also Natorp, Einlcitung in 
die Psychologic^ nach Kritischer Method?, p. 128. 



4 o 

ments in knowledge, holding them in a unity, which alone 
made empirical knowledge possible. This meant, however, 
the extension of logical validity and necessity to empirical 
judgments as well. 

It is, however, by virtue of the transcendental logic of 
the catagories, that function in the Intuition and the Under- 
standing, that this conditional necessity exists. The Tran- 
scendental Logic without the content of the intuition could 
not give necessary relations ot the " Intelligible World," nor 
could necessary relations of the empirical world be found in- 
the content of the Intuition alone. "Concepts without 
intuition are empty, intuition without concepts blind." 
Concepts and Intuition, " Begriffe und Anschauung" are 
together the sphere of the functioning of the Law of Ground, 
and its conditioned necessity. Separated, they are incap- 
able of relations of ground and consequence. This principle, 
which may be called the "Balance of Concept and Intu- 
ition" in Kant's formulation of the " Law of Ground" repre- 
sents his critical position strikingly and is a point of view 
from which the preceding and following formulations may 
be studied. 

£42. Such a study would show that Kant stands as a crit- 
ical mediator between two possible formulations of the Law 
of Ground, that which confines it to the sphere of the formal 
logic of concepts, to the exclusion of the intuitional side, and 
that theory which, excluding the conceptual element, makes 
it a law of the Intuition, "Anschauung." Both of these one- 
rided developments are dogmatic, and in the historical 
development which is the substance of the present study, 
represented by Wolff in the one case and Schopenhauer in 
the oilier. The nature of Wolffs (and before him Spinoza's) 
dogmatism was seen to be the postulating of metaphysical 
validity for merely formal logical relations of concepts. 
That of Schopenhauer, we shall see, lies in postulating the 
Validity of the Law of Ground in the simple intuition, inde- 
pendent of com 'pis. The Transcendental Logic of Kant is 
>nd both these dogmatisms, and protests against both. 



41 

§ 43* This is the second historical point of importance, this 
critical balance of Kant between two possible extremes of 
dogmatism. The Law of Ground is certainly a logical 
postulate, but it is not a principle of merely formal logic. 
Secondly, while the postulate of ground is not a law of 
formal logic, it is not therefore unlogical, and non-concep- 
tual, as Schopenhauer later maintained. Already in Kant's 
life-time an attempt was made to do away with this critical 
balance of conceptual and intuitive knowledge, held to- 
gether by the concept of a Transcendental Logic. Eberhardt 
sought to restore the uncritical philosophy by a doctrine of 
li Intellectuelle Auschauung " according to which all knowl- 
edge of relations is intuitional. It is of interest to us only 
to see how Kant answers this heresy against the " Kritik," 
In his answer to Eberhardt, 1 (Ueber eine neue Entdeckung 
nach der alle Vernunft-Kritik entberhlich gemacht werden 
soil" Kant points out very clearly the conceptual logical 
nature of all relations of ground and consequence, showing 
that the simple elements in space and time, the point, and the 
concepts of cause and effect are all abstractions and therefore 
conceptual in nature. The whole problem is how we shall 
define " Intuition" — but it is clear to Kant that it is not 
intellectual in its nature, but expresses only the manner in 
which we are affected by the unknown thing in itself. 

SCHOPENHAUER. 

§44. The classical formulation of the Principle of Sufficient 
Reason is the " Vierfache Wurzel des Zureichenden Grundes"' 

1 Hartenstein, Kant's Complete Works, Vol. VI, p. 18. "Die einfachen Elemente 
der Anschauung liegen vollig auserhalb der Sinnlichkeit," are intellectual and con- 
ceptual. It becomes certain therefore that "das Einfache, (der Punkt) als Grund zu 
der Anschauung in Raum und Zeit, hinzu vernunftelt ist." We have then this 
dilemma before us — " Eins von Beiden, entweder die Anschauung ist der Anschau- 
ung nach, ganz intellectuelle d. i. wir schauen die Dinge an, als sie an sich sind und 
die Sinnlichkeit besteht lediglich in der Verworrenheit ; oder sie ist nicht intellectuelle, 
wir verstehen darunter nur die Art wie wir von einem, an sich uns unbekannten Object 
afficiert werden." The concept " Intellectuelle Anschauung" is then a contradictioa 
in adjecto and arises alone from an attempt to extend Sufficient Reason where it does, 
not belong, i. e., by making it a law of Objective Reality itself, which we intuit. 



Historically, however, the differentiation of the four roots 
or forms of the principle goes back to Crusius, while the 
content poured into the moulds is entirely Kantian. The 
points of striking dissimilarity between Kant and Schopen- 
hauer are ; a) the manner in which Schopenhauer gives a meta- 
physical significance to the specialization of the four forms 
of ground, while with Kant the distinctions were not funda- 
mental, b) The fact that in Schopenhauer the logical nature 
of the postulate of Sufficient Reason is entirely denied, and 
consequently a constant war is waged against Kant's Trans- 
cendental Logic, c) Schopenhauer's doctrine of Sufficient 
Reason as a principle of intuitive knowledge instead of 
logical thought. The tendency of his entire thinking may 
therefore be summed up as entirely in the direction of a 
metaphysical formulation. 

§45. The crucial point in Schopenhauer's doctrine of 
Sufficient Reason is his theory of the specific nature of the 
four different kinds of necessities in the relations of space and 
time, of causality, of logic or conceptual thought and of will 
motives. It has been the mistake of past thinking, he insists, 
that, in following the natural impulse to unification, it has 
been taken for granted that there is only one Law of Ground, 
and one order of necessity, while in reality, the principle of 
S. R. is only " ein gemeinschaftlicher Ausdruck fiir vier 
ganz verschiedene Verhaltnisse," l each of which has its own 
particular necessity. These four entirely different phenom- 
enal expressions of the law of ground are determined by an 
inductive study of the ideal content of consciousness. The 
method of this specification, as he explains in the paragraph 
On method,- follows the Kantian division of kinds of knowl- 
edge (Erkentniss Kriifte) into Sinnlichkeit, Verstand, Ver- 
nimlt and Wollen. Kant had indeed followed such a divi- 
sion, and had, as we have already seen, 3 developed in the 
" Grundsa'tze " the different forms, which the general prin- 

'" Vier f ache Wuruel" ^52. 
' " Vier f ache WurMel" §§ 1, 2. 
5 < f. paragraph* 35, 36, 



43 

ciple of ground assumes in its empirical use ; and before him 
Crusius had likewise, besides the fundamental distinction 
between real and knowledge grounds, distinguished among 
real grounds those of being, spatially and temporally deter- 
mined, of becoming, causally determined, of will, or motive 
grounds. But it cannot be denied that what, with Crusius 
and Kant, especially the latter, was more a matter of 
schematism and definition, Schopenhauer, in somewhat 
scholastic fashion, makes fundamental and metaphysical. 

§ 46. The development of this theory of the specific neces- 
sities of different kinds of relations of ideas, leads to the dif- 
ferentiation of four distinct classes : 1 . The relations of space 
and time, transcendental and a priori, are so given in the 
intuition, that certain relations of points, given in space or 
time, determine the place of others in the intuitional complex. 
This is the Law of Ground of Being, and upon it is based the 
whole of mathematics, geometry upon the spacial and arith- 
metic upon the temporal necessity. Out of this position the 
theory naturally follows, and it is one which Schopenhauer 
maintains with especial interest, that geometrical reasoning 
is not a logical process, but that its necessity is a matter of 
intuition. 1 The relation of this theory of the Law of Ground 
of space and time relations, to Kant's " Axiome der Anschau- 
ung " is evident. 2 

2. Causality, or the Law of Ground of Becoming, is that 
*a priori relation among ideas, by means of which " ein un- 
mittelbares, intuitives Auffassen der ursachlichen Verbind- 
ung " is possible. Something more than the temporal 
relations of succession is expressed in the causal judgment. 
It is the specific necessity of the causal relation, but it is not 
a conceptual logical postulate reflectively applied to the 
phenomenal subjective succession, thus giving it empirical 

Schopenhauer himself admits, " Welt ah Wille, Sec" page 150, that only the 
recognition, the " cognitio" of geometrical necessity, is intuitive. The proof or " con- 
victio " is logical. This theory of mathematics is of course now discredited. The best 
discusssion of the problem is in the second volume of Wundt's Logic. 

1 Cf. \ 35. 



44 

objectivity, as in the theory of Kant, which we have studied. 
" Matter is through and through causality," but this caus- 
ality is already given in the intuition of matter, for matter 
is defined as ideas in this necessary a priori " togetherness." 
We have not the space to develop further this theory of 
causation, which comes so near to an identification of 
causality with mere temporal succession on the one hand, 
and to a materialistic metaphysic on the other. For our 
historical study the important thing is the exclusion of the 
logical element from the causal concept, which is character- 
istic of Schopenhauer's theory. 

3. The third phenomenal manifestation of the Law of 
Ground is that of the Will in motivation. This is the 
" Causalitat von innen gesehen " */ that is : the same necessary 
binding together of ideas, which, from an objective stand- 
point, we call causality, is from the point of view of sub- 
jective worth, experience, sufficiency of motive. Causal 
necessity expresses itself directly in the subjective grouping 
of ideas only as motivation of the Will. Both the special 
theory of the Will developed b)^ Crusius 2 and the Kantian 
distinction of the empirical from the transcendental WilL 
were important historical antecedents of Schopenhauer's 
doctrine. The source of knowledge of the Will causality is, 
as in the preceding two forms of the Law of Ground, direct 
immediate intuition. 

£ 47. The three kinds of real grounds thus described are, 
according to Schopenhauer, known by us directly in an In- 
tellectual Intuition and are not the result of an application of 
a logical postulate to phenomena. There is, however, a class 
of ideas in which a logical principle of ground is discovera- 
ble. These are the abstract ideas or concepts. Schopen- 
hauer's nominalist ic doctrine of abstract concepts, and the 
absolute distinction he makes between " Begriffe " and 
" Vorstellungen " is the basis for the most fundamental dif- 
ferentiation of [deal and real grounds. While knowledge of 

1 " Vierfacht Wuruel" \>. 163, £ 43. 

■Cf. I 2< } . 



45 

the latter is immediate and intuitive, the former are dis- 
coverable in the norms and laws of formal logic. But since 
logical processes are confined to the formal manipulation of 
concepts, out of which the intuitive element of reality is 
abstracted, they can give no real knowledge. Beside the 
categories of formal logic, Identity, Contradiction and Ex- 
cluded Middle, there is another class of metalogical truths, 
which constitute the conditions of the possibility of all 
knowledge, in the broadest sense. 1 These are the meta- 
physical categories of dependence, which function both in 
the intuition and in conceptual thought. Identity and Suf- 
ficient Reason are the typical categories of this sphere. 

§48. Sufficient Reason he speaks of as a metalogical truth 
par excellence, which functions unlogically in space, time, 
causality and motivation. It is not only transcendental, but 
logically prior to all the empirical expressions of the Law of 
Ground. 2 Its secret lies hid in that metaphysical knot, th 
Subject-Object relation, and we can only come to it through 
" eine Selbst-Untersuchung der Vernunft," which would 
disclose this truth as the condition of the possibility of all 
mental life. 3 Thus is the unitary nature of the law still 
retained. Just how Schopenhauer conceives this unitary 
metaphysical principle is a problem which, when answered, 
will disclose both his relation to the Kantian formulation and 
to the question of the logical nature of Sufficient Reason as 
a universal postulate. 

§ 49. Kant, likewise, had defined the Law of Ground, 
which he calls " das oberste Principium aller synthetischen 
Untheile," as metalogical in contrast to the analytic nature 
of formal logic. He defines the general principle as one coex- 

lil Vierfache Wurzel" § 29. 

2 Cf . " Vierfache Wurzel," §35, where he says: " Daher bin ich in dieser 
Abhandlung bemliht, den Satz vom zureichenden Grande als ein Urteil aufzustellen, 
das einen vierfachen Grand hat, nicht etwa vier verschiedene Grande die zufallig auf 
dasselbe Urteil leiteten, sondern einen vierfach — darstellenden Grand den ich bildlich 
Wurzel nenne." 

3 But " Konnte das Subject sich selbst erkennen, so wiirden wir auch unmittelbar 
und nicht erst durch Versuche an Vorstellungen jene Gesetze (metalogische) erkennen." 



4 6 

tensive with the necessary " Zusammenhang" of all phenom- 
enal reality, as was shown by his very broad formulation of 
it. 1 But, as we have seen, he contended that the law was in 
essence a logical postulate, developing- in the Deduction of 
the Categories what was called the Transcendental Logic. 
Schopenhauer, however, denies a logical character to this 
unitary principle, logic being confined, according to his nar- 
row formal view of it, to only one class of ideas, namely, 
abstract notions, according to his nominalism, with no 
relation to reality. 

§ 50. The only unitary characteristic which is present in 
all these specifications of the Law of Ground, these ' i vier ganz 
verschiedene Verhaltnisse," is the universal form of time. 
Temporal succession is the last term of all experience, the 
ever present formal side of every particular expression of S. 
R. This identification of the general metalogical principle 
with temporal succession comes about in the following way : 
Schopenhauer, following Kant, identifies the Law of 
Ground with the general postulate of a necessary connection 
among all elements of empirical reality, among all phenomena, 
and makes it coextensive with phenomenal reality, defining the 
relation of subject to object in the Kantian manner. 2 But 
while with Kant the subjective flow of ideas becomes empir- 
ical reality by virtue of the Transcendental Logic (which 
includes the entire category-doctrine) with Schopenhauer the 
unitary principle of objectification is temporal succession 
conceived of as a metaphysical transcendental principle. 
" Die Zeit ist das Einfache, nur das Wesentliche enhaltende 

1 Kritik der Reinen Vernunft^ Reclam, p. [55, § 4 : " Ein jeder Gegenstand steht 
unter den notwendigen Bedingungen der synthetischen Einheit des Manigfaltigen in 
einer mftglichen Erf aiming." 

J " Vierfache Wwrnel" % 16: " Unser Bewustsein soweit es als Sinnlichkeit, 

ad and Vernunft erscheint, zerfallt in Subject und Object und enthalt (bis 

dahin) nichts ausserdem ; Object fur das Subject sein und unsere Vorstellungen sein 

ist dasselbe. A lie unsere Vbrstellungen sind Objecte des Subjects und alle Objecte des 

ts sind iin Uungen. Aber (so mussen wir fortahren) nichts fur sich 

and Unabh&ngiges, audi Nichts Einzelnesund Abgerissenes, kann Object 

fur uns werden, aondern nur In einer gesetzmassigen und, der Form nach, a priori 

mmbairen V< rbindung.*' 



47 

Schema aller Gestaltungen des Satzes vom Grunde." l For 
the Law of Ground to be fulfilled something must always 
precede, as cause, or warrant, or motive ; and this preceding is 
the formal condition for the finding of a Sufficient Reason for 
what follows. 

§51. In finding the universal principle of S. R. in tem- 
poral succession, Schopenhauer does not of course mean mere 
psychological succession. Kant's criticism of Hume had 
shown that mere succession could not be raised to the neces- 
sity of ground and consequence. The alternative therefore 
is either to accept the logical element, as a postulate thought 
into the mere temporal succession, or excluding the logical 
element, to raise temporal succession to a metaphysical 
principle, and with it the Law of Ground as identical with 
succession. This Schopenhauer did, and in so doing made 
Sufficient Reason a purely metaphysical law. Two doctrines 
naturally follow from this theory : 

1. Logical relations are reduced to one of the four 
specific forms of succession, and made only one of the four 
principles of ground. 

2. Since the knowledge of these phenomenal manifesta- 
tions of S. R. is not obtainable through logical reasoning, 
that is in the application of logical postulates to empirical 
reality, some new principle of knowledge other than logical 
must be sought. This necessity Schopenhauer's theory was 
able to meet by means of his doctrine of " Intellectuelle 
Anschauung." In intuiting ideas in their temporal succes- 
sion we intuit likewise their necessary relations either as 
cause and effect, as motive and will act, as ground and con- 
sequence. In this doctrine of the intuition of grounds and 
consequences, we have the necessary outcome of Schopen- 
hauer's theory of Specification. 

§ 52. All the elements of Schopenhauer's theory are now 

1 Vierfache Wurzel, §§ 46 ; 143. And again § 52, he calls it : " Der immanente 
Keim aller Dependenz, Relativitat, Instabilitat und Endlichkeit in unserem subject- 
object befangenen Bewustsein .... welche das Christentum mit richtigem Sinn die- 
Zeitlichkeit nennt." 



4 8 

before us. On the one hand, the empirical manifold of the Law 
of Ground, in so far as it is entirely empirical is reduci- 
ble to the one common term of temporal succession. This 
common element, empirically considered, contains no princi- 
ple of determination, however, other than psychological 
necessity. The peculiar necessities of the three different 
spheres of Causality, Space and Time and logical relations, 
are only explainable as expressions of one metalogical or 
ontological principle of determination, which is the Subject- 
Object relation itself. This identification of the metalogical 
Sufficient Reason with temporal succession is only explaina- 
ble in the light of the general metaphysical system of which 
Schopenhauer's peculiar doctrine of S. R. is an element. 
The phenomenal objectification of the Ontological Will, 
which is at the same time the origin of the world and of the 
knowledge of the world, is in its first stage temporal succes- 
sion, and this temporal succession is the logical prius of the 
particular necessities of the different spheres of the mani- 
festation of this primal law. The phenomenal objectifica- 
tion is Sufficient Reason as a metalogical principle. This 
much of Schopenhauer's Ontology is sufficient to make clear 
the relative place of the logical Law of Ground and of the 
causal axiom in his theory. 

In that Sufficient Reason is at the same time the principle 
of the phenomenal objectification and of the knowledge of 
that objectified phenomena; knowledge and reality are the 
same process. " Die Welt ist meine Vorstellung," «* Object 
tiir das Subject sein und unsere Vorstellungen sein ist das- 
selbe." Causality is an a priori, not simply regulative, but 
constitutive Sufficient Reason ol the existence of objective 
reality. " Materie ist durch und durch Causalitat." 

$53. Now Kant had likewise found in the causal axiom, 
the Sufficient Reason of phenomenal reality — the law of the 
binding together of phenomena, but as an axiom of knowl- 
edge the causal principle was conceived to be partly a logi- 
cal postulate, The logical deduction of the categories aims 
to show that though transcendental, they are yet logical in 



49 

their essence. This reflective theory of the movement of 
Sufficient Reason in the temporal flow of phenomena, de- 
scribed by Kant in the " Deduction," was constructed, 
Schopenhauer maintains, " um innerhalb der Transcendental 
Logik zu bleiben." l This logical standpoint Schopenhauer 
abandons. 2 Since objective reality and the knowledge of that 
reality are the same, a unitary movement of Sufficient Reason 
in the causal principle, the reflective logical element in the 
principle of ground is discarded as superfluous, and in its place 
is substituted a unitary non-reflective function called the " In- 
tellectuelle Anschauung." This Intellectual Intuition then, 
as an immediate perception of the relation of ground and 
consequence in reality, independent of reflection and logical 
thought, is a necessary mysticism growing out of the identi- 
fication of the reality of objective existence and its relations 
with the necessity of the knowledge of that reality. As a 
consequence, the whole Kantian attempt to show (in the 
psychological Subjective Deduction) how the postulate of 
logical thought necessity may combine with sensational 
reality in a transcendental material judgment is vain. In 
the Intuition we have reality and intellectual necessity at 
the same moment. 3 

§ 54. This identification of the modal categories of reality 
and necessity which Kant had distinguished so carefully, is 
typical for the whole standpoint, and follows logically from 

Appendix, " Welt als Wille, &c." Haendel, p. 36. 

2 Konig, {Entwickelung ties Causal-Problems," Vol. II, page 32), makes the 
criticism that the general principle of Ground is developed merely as a formula for the 
whole sphere of ideas. Since a Deduction of the law fails both for the general law 
itself and for the particular cases of the law, it can be looked upon only as an empty 
formula for a number of incommensurable relations. This must necessarily follow if 
the essence of the principle, its logical element, is discarded. 

3 " Die Welt als Wille, &c." Haendel, p, 17. " Daher auch erregt die anschau- 
liche Weltf so lange mann bei ihr bleiben steht, im Betrachter weder Skrupel noch 
Zweifel ; es geibt hier weder Irrthum noch Wahrheit ; Diese sind ins Gebiet des 
Abstracten, der Reflexion gebannt. Hier aber liegt fiir Sinne und Verstand die Welt 
offen dar, giebt sich mit nai'ver Wahrheit fiir das was sie ist, fiir anschauliche Vor- 
stellung, welche gesetzmassig am Bande der Causalitat sich entwickelt." 



5o 

his metaphysics. 1 It is the complete negation of the criti- 
cal standpoint, which has as its chief problem the deter- 
mination of the relation of the logical to the material elements 
in the Law of Ground. The critical balance of Kant, is 
overthrown in favor of a metaphysical dogmatism. 

>' 55. Schopenhauer's doctrine of Sufficient Reason was 
intended to make clear in a technical and scientific way, what 
his entire philosophical attitude continually implied, namely 
the insignificance of logical reflection in our knowledge pro- 
cesses. Theoretical logical necessity, he is continually 
announcing, is but the appearance, the shine of knowledge. 
The direct intuition in which no contradictions appear is the 
only real source of truth. Aside from the general weakness 
of a position such as this, which invalidates the entire logical 
concatenation of his own system, we are interested chiefly in 
understanding what, from the standpoint of development, 
results for our special problem of the Law of Ground, by 
such a negation of the logical consciousness. 

§ 56. If we keep in mind the general trend of our study — 
that Post Leibnitzian thinking displays an interaction and 
often struggle between the logical and metaphysical motives, 
both prominent in Leibnitz's formulation of Sufficient Reason, 
and secondly that the Crusius-Kantian movement represents 
a development of the metaphysical motive, it will be clear 
that Schopenhauer's modification of the Kantian philosophy 
is the extremest possible putting of the anti-logical tendency. 
The logical consciousness is reduced to a minimum of range 
and value. Logic is only formal and, in that it deals only 
with nominalistic concepts, mere shadows of the real, it has 
only symbolic value. Not only is the essential logical nature 
oi the Law of Ground denied — but logic ceases to be even an 

ntial side of the Law. 

1 'I bus in his " Kritik <(<>■ KanHschen Philosophic" " Alle diese Umstande (die 

Begriffe Moglichkeit, Ummoglichkeit) daher stammen keineswegs aus einer (leistes 

tides, sondero entstehen durchdeo Conflict des Abstracter! l.rkennens 

mit dem Intuitiven wie man gleich schen win] " — and again on p. km, " Demgem&ss 

Wirklich zugleich eta Notwendigea und in der Realitat zwischen Wirklichkeit 

endigkeit ist kein Unterschied und eben so keiner zwischen Wirklichkeit 

und Moglichkeit." 



5i 

§ 57- This very radicalism of Schopenhauer's doctrine 
makes it of particular value in the present study — as a crucial 
and turning point — so to speak, in the development of the 
principle under consideration. For what is the Law of 
Ground, if not a knowledge principle — and what is a knowl- 
edge principle if not in some way connected with the logical 
consciousness, and its reflective processes. Again the notion 
of Sufficient Reason is in contradiction with the idea of 
knowledge in a unitary Intuition. The relation of ground 
and consequence, implies the analytical severance of two 
distinct elements, the ground and the consequence. This 
analytical abstraction must necessarily result in thinking the 
ground and consequence conceptually. As Kant says, " Die 
einfachen Elemente der Anschauung liegen vollig ausserhalb 
der Sinnlichkeit und sind conceptual." 1 The concept of 
Intellectual Intuition and the relation of ground and con- 
sequence are therefore absolutely contradictory ideas, for 
the latter relation is analytical as succeeding thinking fully 
demonstrated, while intuition describes a movement of con- 
sciousness unitary and synthetic, in which no differentiation 
of parts arise. Kant then did well in remaining " innerhalb 
der Transcendental Logic" 2 — that is in extending his concept 
of the logical consciousness to include Sufficient Reason — 
and it cannot be a matter of wonder that he was almost 
scornful in his condemnation of Eberhardt's doctrine of "In- 
tellectuelle Anschauung" as destructive of all critical think- 
ing. Schopenhauer's negation of the logical consciousness, 
and formulation of Sufficient Reason as a process of metalog- 
ical Intuition is a mysticism which may be very properly 
called the reductio ad absurdum of the anti-logical, metaphy- 
sical tendency in the history of the Principle. 

1 Cf. Note, page 41. 

2 Appendix " Welt a Is Wille 6° Vorstellung" p. 36. 



52 



CHAPTER V. 

The Conflict Between the Metaphysical and Logi- 
cal Doctrines of Sufficient Reason. 

§ 58. Schopenhauer's formulation of Sufficient Reason 
received the preceding full treatment in view of the fact that 
in several important respects it stands as typical for the 
whole movement from Leibnitz on, and secondly because it 
contains the best expression of the contradiction out of 
which the modern logical theory arose as necessary conse- 
quence. 

§ 59. Looking backward, it may not be too much to say 
that this classical formulation stands as a reductio ad absur- 
dutn of the principle which characterized the preceding 
movement. For Schopenhauer's doctrine is the most con- 
sistent answer to the Leibnitzian demand that a Principle of 
Sufficient Reason be found for empirical reality that should 
lie outside the sphere of logic. Leibnitz had in mind a Law 
of reality itself — and identified Sufficient Reason with 
causation, but there was also implicit in the idea of Sufficient 
Reason, a notion of a new principle of knowledge of empirical 
reality other than the logic of concepts. But if we assume 
a causal law in reality independent of our knowledge, — our 
knowledge of that causal relation can come about alone in 
one of two ways, either through logical thought, or through 
immediate intuition of these causal relations. This contra- 
diction made itsell felt immediately in the successors of 
Leibnitz. Already Wolff champions the logical formulation 
of the law, while Crusius leans toward a view, according 
to which our knowledge of causal and will relations is of an 
un logical nature, although he does not come to a clear form- 
ulation oi the nature of thai knowledge. Kant again made 
nthesis of the two sides, in thai instead of the simple 
"sufficiency" ol Leibnitz he demanded a determinism for 



53 

our knowledge of empirical reality, but not the determinism 
of formal logic. In its place enters a doctrine of a Transcen- 
dental Logic in which the intuitional and conceptual elements 
are critically balanced. This temporary balance was neces- 
sarily disturbed by the succeeding movements, the Hegelian 
movement falling back upon the formal side of Kant's Tran- 
scendental Logic, Schopenhauer taking the intuitional side 
to the exclusion of the logical conceptual element. In that 
the Sufficient Reason of empirical reality is given directly 
and immediately in the sense intuition, is the Leibnitzian 
demand first consistently answered — the demand that the 
principle of empirical knowledge lie outside the conceptual, 
logical sphere. 

§60. But in that this stage is reached, is the impossibility 
of such an answer evident. For the doctrine of an imme- 
diate intuition of the empirical Sufficient Reason, once 
clearly formulated, proves itself to be in direct contradiction 
to the idea of the relation of ground and consequence — as 
Kant already protested against Eberhardt, and as fully 
pointed out in the case of Schopenhauer. This contradictio 
in adjecto in the conception of the intellectual intuition of 
the ground and consequence is the reditctio ad absurdum, 
which shows us the impossibility of a relation of ground and 
consequence other than logical. 

§61. After Schopenhauer a marked change is evident 
in the attitude of thought to our principle, a change which 
appears as a historically and logically necessary consequence 
of the failure of the first movement. This change is in the 
direction of a logical formulation of Sufficient Reason, not 
logical in the sense that it is subordinated to the Principles 
of Identity and Contradiction, as with Wolf, but rather in 
that it becomes the basal principle of logic to which the laws 
of Identity and Contradiction are subordinated. In this 
movement two stages may be distinguished: 1. The struggle 
between metaphysics and logic, as represented in Herbart 
and Trendelenburg, and 2) the completed formulation of the 
law as basal principle of logic in Sigwart and Wundt. The 



54 

most obvious motive to such a return to a logical view of 
Sufficient Reason, is the recognition of the impossibility of 
any other than a logical conception of the relation of ground 
and consequence. An unusually strong motive is the appear- 
ance of a distinct trend toward scientific method in Philoso- 
phy. The logical possibility of the relation of cause and 
effect, and the possibility of a unity of the "thing" among 
its many attributes, — these are the metaphysical problems 
which most concern science. 

HERBART. 

^62. It becomes then the problem of a theory of knowl- 
edge, in touch with the new scientific consciousness, to 
subject the fundamental concepts of science to critical analy- 
sis. We are led herewith to a new attitude and a new 
method in philosophy — which makes itself immediately felt 
in the new turn given to the formulation of Sufficient 
Reason in Herbart's thinking. This may be described 
briefly as a conflict between a logical and metaphysical form- 
ulation, in so far as the Law of Ground is concerned. 
Protesting against a certain formalism and abstraction in 
the Kantians, according to which general a priori laws of 
empirical thought, a sort of mechanism, are set over against 
the concrete activity of mind upon concrete problems of 
scientific thought, Herbart sets himself immediately to the 
solution of the problem of the relation of ground and conse- 
quence as such. The Methodologie or the first part of his 
Metaphysik, is concerned entirely with the Principle of 
14 Sufficient Reason," the third chapter of which he begins 
with this sentence: " Die erste aller Fragen fiir den welcher 
durch Speculation sein Wissen erweitern wollte war unstrei- 
tig die; w ie folgl Kins aus dem Anderen? Was ist ein 

( j rund ; Was heissl eine Folge? " 

' .lb- finds, in answering these questions, that formal 
■ has tailed entirely to show how the relation of ground 
and consequence is thinkable, since it contains the contra- 
diction of assuming that its concepts are definitely determined 



55 

quantities, and yet demands in the Law of Ground that 
the consequence be something new, else it does not consti- 
tute a widening of knowledge. But if the consequence is 
new, it was not contained in the definitely known concept, 
called the ground. Thus the principle of ground must as a 
method of widening our knowledge lie outside the formal 
logic of definite concepts. 1 This, however, is nothing more 
than the Kantians had discovered, but their substitutions in 
place of the failure of formal logic are equally unsatisfactory 
to Herbart. First of all, the Law of Ground was sup- 
posed to be explained when a certain number of a priori 
subjective forms were shown to be the logical pre-supposi- 
tions of all experience, but this is a subjectification of the 
problem which Herbart will not allow, and likewise an un- 
warranted generalization, for the problem of ground and 
consequence is always the question of definite empirical rela- 
tions, of the possibility of one element being thought the 
ground of the other, and any attempt to deduce these formal 
relations in experience from a priori knowledge forms leads 
to blindness in regard to the problems of each particular 
relation. 2 The problem of knowledge is not how according 
to the nature of our knowledge functions, it is possible for 
us uberhaupt to know, but rather is the world of experience 
given us in its complex of form and content, and this we 
must so reconstruct as to make it rational. 3 

§64. Equally true is it that the " Intellectuelle Anschau- 
ung" fails to answer the problem. Immediate intuition 
cannot give the evidence which belongs to relations of 
ground and consequence. To be sure it gives us ideas and 
relations, which we must hold fast to, although logic 
threatens to abandon them, but we cannot fall back upon the 
sloth of " diesen Schwarmern " who will not think the prob- 
lem through but claim that the relation of ground and 
consequence is given in the "Anschauung." 4 The contra- 

1 Herbart's Complete Works, edited by Kehrbach. Vol. VIII, §166, p. 15. 

3 Complete Works, Vol. VIII, p. 22. 

3 Complete Works, Vol. VIII, p. 18. * Complete Works, Vol. VIII, $185, p. 38. 



56 

dictions which arise in the immediate intuition must be put 
aside by logical thought. 1 Historically, Herbart had in mind 
in these introductory criticisms, besides Kant himself, the 
logical rationalism of Hegel and the Intuition theory of 
Schelling's Natural Philosophy, but if Schopenhauer had 
been a ruling thinker of the time, his intuitional view of the 
relation of ground and consequence would not have escaped. 

§65. The failure of all these thinkers, he continues, has 
been that they have invariably assumed the possibility of the 
relation of ground and consequence ; and this has been the 
root of so many profitless generalizations. 2 An analytical 
study of the logical possibility of the relation itself is the 
first step, and from this the conclusion is reached that the 
principle of Sufficient Reason is first of all a subjective 
postulate arising out of a contradiction between the intuition 
and our concepts already developed — a postulate which de- 
mands the removal of these contradictions and may be 
expressed as a demand for a contradictionless whole of expe- 
rience. 3 The possibility of the satisfaction of this impulse, 
of the solution of these contradictions, lies in the possibility 
of so extending the meaning of the general concept as to 
make a new ground, a new complex of ideas in which the 
contradictory element of experience may be seen to be con- 
tained. This concept of the solution of the contradiction 
between ground and consequence, by widening the ground, 
is further developed in his so-called " Methode der Bezieh- 
ungen" of which it is necessary for us to get some notion. 

§66. While Herbart, recognizing the contradiction in- 
volved in the subsumption of the Law of Ground under 
the norms of formal logic, denies the sufficiency of the latter, 
he yet recognizes in the demand of Sufficient Reason for 
a contradictionless whole of experience, an essentially 

x Complete Works, ' / /.\<)2, p. 46. 

5 r&s, Vol. VIII, p. 4.14. — " Meine Untersuchung," he says in his 

reply to tin: criticism <>f Prof. Brandis, "stellt aber die ^m/.c Moglichkeit classes 
tiberhaupt Grttnde geben Iconne, von vora herein in Zweifel ; und bier wenn irgendwo, 
ist, mcincs Erachtens, Zweifel der Wei?hei1 Anfang." 

■ Compute Works t Vol. VIII, p. 23. 



57 

logical nature. The problem of his analysis is so to investi- 
gate the possibilities of logical relations, so to widen the 
notion of logical ground, one might say, as to make the 
relation of ground and consequence a logical possibility. 
Since the contradiction arises out of the relation of the con- 
crete particular to the abstract concept, the first problem is 
that of the relation of the two. This is, according to his 
theory, purely nominalistic. General concepts are but 
short-hand registers for the real, by means of which the 
" manifold " of the given may be grasped in a unity. 1 Formal 
logic can, therefore, of necessity give only schematic rela- 
tions, in which the manifold of the real cannot be contained 
without contradictions. But in that these concepts are only 
symbols they may be changed to suit the requirements of 
the particulars with which they are in contradiction. The 
laws of formal logic remain their only governing principles, 
under the more primal postulate which includes all of expe- 
rience, for the material side has as its problem the continu- 
ous widening of the general concepts to meet the require- 
ments of particular experiences, in order that a logic of 
concepts may be a logic of reality. 

§67. Instead of the principle of Subalternation which 
determines this relation in formal logic, in the broader view 
of logical necessity which this doctrine of Sufficient Reason 
compels, a new principle must be sought. This, the "Meth- 
ode der Beziehungen," consists in so widening the concept 
by adding elements, that the consequence may be seen to be 
necessarily contained in it. 2 This proceeds by chance sug- 
gestions, " Zufallige Ansichten," that is of new possibilities 
which lie hidden in space and number relations which serve 

1 Complete Works, Vol. VIII, p. 15. 

2 Complete Works, Vol. VIII, §§ 174, 175. Especially the example of the solu- 
tion of the Pythagorean problem of the right-angled triangle (by dropping a perpendic- 
ular upon the hypotheneuse, by means of which the concept of the right-angled 
triangle together with the added concepts developed by the dropping of the perpendic- 
ular, form the whole ground of the consequence that all the angles equal two right 
angles) shows the nature of the process, and is in itself proof against the Schopen- 
hauerean theory that ground and consequence are here found by means of Anschaimng, 



58 

as a means of helping on the deduction. " Diese Kunst- 
griffe enweitern den Grund aus welchem die Folge hervor- 
gehen soil. 1 The conclusion, which is the matter of great 
importance for an historical study, is simply this: that the 
ground is never one definite concept but a changing com- 
plex of concepts, a system, the dependence of one concept 
from another being the necessity out of which the norms of 
formal logic get their material. The Law of Ground is there- 
fore an immanental law of all conceptual interdependence, 
and as such the presupposition of the analytical laws of Iden- 
tity and Contradiction. 

§ 68. When this theory of Sufficient Reason is con- 
trasted with the Kantian point of view the most striking dif- 
ference is found to lie in the fact that while the latter, to 
escape the contradictions and insufficiencies of formal logic, 
is driven to a metaphysical formulation, in which the logical 
nature of the law is recognized only as a transcendental ele- 
ment, with Herbart these same difficulties of formal logic 
are overcome without deserting for a moment the logical 
point of view, but merely by broadening the notion of logical 
dependence and by the introduction of the concept of a 
" widened ground." 2 This difference is likewise reflected in 
Herbart's energetic protest against the point of view which 
assigns to the judgment of ground and consequence a syn- 
thetic rather than analytic nature. The analytic of formal 
logic is continued in the analytic by means of which the 
immanental relations in the larger ground are discovered, 
and by means of which the contradiction is solved, for this 
analytical process must occur as often as our attempt to 
fasten a relation in thought develops contradictions. In his 
second letter in reply to Brandis' criticisms' 5 he points out 
that it is not the judgment of relations of ground and con- 
sequent <• thai is synthetic, but only the immanental depen- 
dence or Zusammenhang which underlies this judgment. The 
judgment ol ground and consequence is itself analytical. 

>■/,/,■ Work., Vol. VIII, I). 25. 

1 Compute Works, Vol. VIII, p. 36. 

1 Complete Works t Vol. VII, Appendix ; also p. .}?, §iqi. 



59 

§ 6g. The second division of our exposition is the applica- 
tion of this theory of Sufficient Reason to reality itself, or a 
consideration of the third " Forderung einer Methodologie," 
that it shall be able to return from its reflexions again to the 
Given. 1 That is, the " Methode der Beziehungen " must be 
:applied in general to a consideration of those chief forms in 
which phenomena manifest their "togetherness," to the 
typical complexes of the " Schein," to see by the abolishing 
of contradictions "vie viel Hindeutung auf Sein " there is. 2 
Now the source of these particular contradictions, according 
to the basal metaphysical principle of Herbart's system, is 
the necessary contradiction between the unity and indepen- 
dence of real being, and the relativity of empirical phe- 
nomena. The fundamental concepts of this latter phenomenal 
sphere are necessarily full of intuitional sense elements, or 
better expressed, psychological in their immediate origin. 
It is the working over of these concepts, in order to free 
them from the contradictions that arise out of these con- 
ditions of their origin, that constitutes the main problem of 
philosophy. It is therefore not in immediate real relations 
but in the possible to thought that final reality is to be found. 

§70. We are not so much interested in the "working 
over" of the particular concepts of Causality, Substance, 
and Inherence, as in the r61e which the Law of Ground plays 
in this connection. The characteristic feature of Herbart's 
concept of logical thinking, and of the function of Sufficient 
Reason is that these are not confined to particular logical 
schemata such as the syllogism or the hypothetical form, but 
the consequence is conceived as springing rather from an 
indefinite and complex system of concepts, the "widened 
ground." This complex and phenomenalistic relation of 
ground and consequence, corresponds then to the complex 
relativity of empirical phenomena, as we have it expressed 
in the 'empirical concepts of Causation, Inherence, &c. The 
analytical working over of these latter concepts, until they 

1 Complete Works, Vol. VIII, p. 14. 

a Complete Works, Hartenstein, Vol. Ill, p. 44. 



6o 

express the logical relation of ground and consequence with- 
out contradictions, is therefore the goal of Sufficient Rea- 
son. The relation of ground and consequence shall like- 
wise make the relations in the real understandable that all 
real connections may be seen to depend upon the logical 
relations of ground and consequence. 

§71. In the working out of this new and modified ration- 
alism it is seen that the concepts of Inherence and Causation 
inevitably carry thought from the appearance to the meta- 
physical ground of the appearance. 1 Especially the causal 
concept, as the result of this analytical determination by the 
11 Methode der Beziehungen," loses the empirical signifi- 
cance which distinguishes it from the logical law of ground. 
Causation as a phenomenon of succession belongs entirely to 
the sphere of appearance. Real happening and the neces- 
sity involved in it are conceivable only as metaphysically de- 
termined. 2 The application of the logical law of ground and 
consequence to experience led Herbart to the belief that all 
thinking concerning phenomenal relations, according to its 
principle, must consist in metaphysical constructions. The 
''Sufficient" Reason of the real is again identified with 
causality. The idea that the empirical as well as the meta- 
physical concept of causality might be an expression of the 
law of ground did not find a place in his thinking. The ideal 
of a contradictionless whole of thought as his ideal of Suf- 
ficient Reason led him into ontology. 

§72. Professor Brandis in his critique properly asks, can 
we consider that, after this method of Relations has done 
away with all contradictions, we have actually come "liber 
die ratio cognoscendi hinaus?" Can it be said that by reliev- 
ing the concept of causality of its contradictions we have 
gotten to the real inner nature of a particular causal relation? 
[s it not rather a " Machtspruch des Denkens" that changes 
the logical result into a knowledge of the real as it is? Asa 
matter of fact, Herbart anticipates this criticism when he 

1 Complete Workt x Vol. VIII, p. 243. 

•Cf. Konig, Entwickelung dei Causal Problems x Vol. II, p. 118. 



6i 

says "unsere ganze Abweichung von der Erfahrung besteht 
in notwendigen Erg'anzungen dessen was sie uns nicht voll- 
standig zeigt." 1 And indeed it does seem that if a contra- 
dictionless whole of experience be the ideal of Sufficient Rea- 
son — that if the nature of the principle is that of a logical 
postulate, then starting with experience as a basis, whatever 
the exigencies of the logical working over of the contradic- 
tions involved in that experience develops, must represent 
the real. But this involves a tremendous assumption which 
no theory of knowledge has a right to make, viz. : that the 
logical consciousness can penetrate to the essence of reality. 
Although Herbart had clearly before him the two distinct 
problems of the logical nature of the postulate of ground 
and consequence on the one hand, and on the other the ques- 
tion of the application of that logical postulate to reality as 
given in experience, yet he did not rise to the point of dis- 
tinguishing between an empirical and a metaphysical appli- 
cation of the Law of Ground, nor did he appreciate fully 
the critical nature of the problem of the limits of these two 
extensions. This remained for a later and more developed 
stage of logical reflection — as represented by the logicians 
Sigwart and Wundt. 

§73. It is at this point that the struggle between a logi- 
cal and a metaphysical view of the Law of Ground, which 
characterizes the Herbartian thinking, becomes prominent, 
namely, in the two problems, on the one hand of the nature 
of the law and secondly the extent of its application to re- 
ality. Arisen as a problem of methodology, defined as a sub- 
jective postulate demanding a contradictionless whole of ex- 
perience, it is further developed into a complete logical and 
analytic method which, without deserting the logical stand- 
point, extends in a critical fashion the concepts cf logic to 
meet the demands of the material elements, for which formal 
logic 'is not sufficient. In the application of this principle 
to the problems of reality Herbart fell back into the ration- 
alistic and ontological point of view, to which his theory was 

1 Complete Works, Vol. VIII, p. 399. 



62 

near akin. For in following out this postulate of a con- 
tradictionless whole of thought, he was led in the way of 
Wolff, that is into the world of the "possible" and not of the 
real, for the former alone can be disclosed by the principle 
of Contradiction unaided by the limitation of the definite- 
laws of experience. It remained for a follower of Herbart,, 
Drobisch, to develop more definitely the logical nature of 
the Law of Ground, and for later thinkers, also influ- 
enced by him, Sigwart and Wundt, to determine more- 
critically the application of the law to reality. It should 
not be overlooked, however, that Herbart grasped the one 
historically important idea, namely, that the Law of 
Ground is essentially a logical principle, with applications to 
the real, and not a metaphysical law of real relations. Per- 
fectly consistently then he distinguishes in the last chapter 
of his Encyclopedia, an indefinite number of grounds, in sig- 
nificant contrast to the fourfold division of which Schopen- 
hauer made so much. 

§74. With the Herbartian School properly closes the 
history of Ratio Sufficiens as a metaphysical principle in the 
strict sense of the term. Now begins a process of disinte- 
gration which makes it somewhat difficult to follow the fate 
of our principle. It would be almost impossible, in the 
midst of this eclecticism that follows, to give a satisfactory 
account of it were it not for a phenomenon which is char- 
acteristic of this eclecticism, but of immense importance to 
the progress of modern thought — namely, the rise of the 
modern ll Erkent7iiss-tkeoretische Logik." In this movement 
Logic comes to a consciousness of itself and its problems — 
of its close relations to psychology, on the one side, and to 
metaphysics on the other. And what is still more important 
to us, this change arises in close connection with the prin- 
ciple of Ground. The Law of Ground as a metaphysical 
principle in the hands of Leibnitz, resisted the logical form- 
ulations attempted by Wolff and his school, which made it 
subordinate to the principle of Contradiction, and passed 
over into the metaphysical formulations of Kant and the 



63 

post-Kantians. But it will be remembered that in the formu- 
lations of both Schopenhauer and Herbart there was a 
psychological element as well. In Schopenhauer's ideal- 
ism this was the principle of dependence among ideas 
in the purely temporal association flow of ideas. Herbart's 
realism, on the other hand, has its psychological side in the 
struggle among ideas to preserve their individuality in their 
mutual interference or "Hemmung." The psychological repro- 
duction in these ideas is simply a picture in consciousness of 
a like condition among metaphysical reals. But the ques- 
tion, how logic shall be related to this principle, has re- 
mained in the back-ground. Wolff had looked upon Suf- 
ficient Reason as equally ontological and logical, but its 
subordination to the Law of Contradiction hid the problem 
contained in it. Besides, according to his thinking, the 
foundations of logic lie in Ontology as well as Psychology. 1 
With the absolute distinction between form and content in 
Kant's critical philosophy, logic became a purely formal 
discipline; consequently Sufficient Reason as the supreme 
law of synthetical material judgments found no place in his 
formal logic. So also Schopenhauer recognizes logic as 
only formal, and only as one of the four forms of grounding 
— which involves him, as we have already seen, in a puzzling 
contradiction. Krug and Kiesewetter continue the formal 
tradition of Kant, and, influenced by them, Sir William 
Hamilton developed a formal logic upon the same lines. 
Under the special influence of Krug, the Law of Ground 
and Causation are both subordinated to the more general 
terms of "Conditioning" and "Conditioned." 2 In his 
"Discussions," however, a later work, the Law of Ground 
is treated merely as a corollary of the three-fold normative 
law of logic, Identity, Contradiction, Excluded Middle. s 
And again (page 603 of the same work) he demands that: 
" The' Principle of Sufficient Reason should be excluded from 
logic. For, inasmuch as the principle is not material, it is 

1 "Logica Discursus Praeliminaris" §88. 

2 Logic, p. 62, 63. * Discussions, pp. 160-603. 



6 4 

only a derivative of the three formal laws, and inasmuch as 
it is material, it coincides with the principle of causation and 
is extra logical." In its essence it is not normative but ma- 
terial. Likewise Herbart 1 and his school aim at a complete 
diremption of formal logic from metaphysics and psy- 
chology, especially Moritz Wilhelm Drobisch. 2 

§75. Against this formal tendency in Logic, as well as 
against the subordination of logic to metaphysics arises the 
41 Erkentniss-theoretische Logik" with the problem of 
following logical forms into their psychological and meta- 
physical sources. As especial originator of this movement 
we may consider Trendelenburg, whose " Logische Unter- 
suduingen" appeared in the first edition in 1840. But 
although this work arose as a distinct protest against the 
formal logic, (whose neglect of the problems of ''content," 
he claims would only be be allowable " wenn die Formen des 
menschlichen Denkens iiber die Wechsel — Beziehung in der 
sonst alle Dinge gefangen sind, erhoben waren" 3 ); yet it is 
equally in opposition to the existent forms of the metaphysics 
of the day as represented in Hegel, Herbart and Schopen- 
hauer. 4 As might be expected from the nature of its ante- 
cedents, this work does actually have as its main problem a 
satisfactory formulation of Sufficient Reason. For it is in 
this principle that the boundary line between logic, psy- 
chology and metaphysics lies. Formal logic cannot deal 
with it alone, because of its material element. If, on the 
other hand, the material element be taken cognisance of, it 
leads us directly into psychology and metaphysics. 

ijG. It is at this point that Trendelenburg's critique of 
preceding systems aims to show wherein these metaphysi- 
cal formulations of Sufficient Reason are untenable. His 
own formulations will include, then, only such material ele- 
ments — metaphysics and psychology — as the proper under- 

1 Einleitung in die PAilos., £34. 

7 Introduction to Third Edition of his Logik. 

% Logische Untersuchunzen, 3d Kdition (1S70), p. 17. 

4 Introduction to Second Edition, 6l, \. 



65 

•standing of the process of knowledge itself demands. 
Whether his metaphysical doctrine of ground be tenable is 
another question. The problem itself is a new one, and an 
important step in modern thinking: Sufficient Reason is the 
basal problem of knowledge — therefore of logic ; it cannot 
be treated alone formally, for it contains material elements; 
just these material elements, therefore, must be included in 
our logic. 

§76. The problem of the relation of ground and conse- 
quence becomes the central point in the Logische Untersuch- 
ttngen. Critically antagonistic to Hegel's identification of 
logic with ontology which, though at first sight it seems to 
offer what formal logic fails to give, really implies that 
thinking is without real presuppositions and of its own 
necessity develops, 1 he is equally critical toward Herbart's 
nominalism, seeing no means by which the " Method of Re- 
lations" can be more than a formal principle, since there is 
no reason why on the basis of this theory the number of ele- 
ments in the "widened" ground should correspond to the 
plurality of metaphysical reals, how the solution of a logical 
contradiction can be the solution of a real discrepancy. 2 
Likewise, in opposition to Schopenhauer, he attempts to 
find a fundamental place for the teleological element in 
Sufficient Reason, as a constitutive element in each of its 
mechanical categories, space, time and causation. 3 

§ Jj. Although Trendelenburg's entire work is in a sense 
an exposition of the Law of Ground, the requirements of our 
historical study, as well as the limitations of space, allow of 
but merely a passing glance. His view of logic as a material 
as well as formal science leads to a doctrine of Sufficient 
Reason which assigns to it likewise a material character. 
The real necessity of the ratio essendi and the merely formal 
necessity of logical ground and consequence have been either 
absolutely separated or fully identified. Neither of these 

x Logische Untersuchttngen, Vol. I., p. 38. 

^Logische Uniersuehungen, Vol. II., p. 397, 399. 

*Logische U titer sue hungen, Introduction to II. and III. Editions, 



66 

extremes ol Schopenhauer or Hegel is necessary. As 
knowledge includes both thought and being, so this basal 
principle of knowledge is equally a real and a thought 
principle. The solution of this contradiction between the 
Law of Ground as a logical principle, and as real necessity, 
is accomplished by a reduction of both to a common lower 
metaphysical term which is yet higher than either. 1 This 
third metaphysical term rejuvenates the Aristotelean theory 
of one primal activity or movement, of which thought and being 
are elements. Applied to the concept of ground, the theory 
seeks to show that in the complete ground elements of 
thought and reality unite to produce the consequence. 

§78. While such a metaphysical hypothesis of a " Grund- 
thatigkeit, 1 " including both thought and being, is an impos- 
sible solution from a logical standpoint, we must carefully 
distinguish this hypothesis from the historical motive which 
brought it into being, and from the logical working over of 
the formal categories which followed as its proof. 1 First of 
all the motive which led to this metaphysical theory was 
that of finding a basis for a theory of logic which would 
include material elements. It was essentially a protest 
against a narrow formal view of logical categories, and 
claiming material necessity for the Law of Ground, it 
sought a widening of the concept of logic. It is not to be 
wondered at that a metaphysical theory was close at hand. 
And, secondly, the working out of the logical categories, 
especially those of modality, developed a phenomenology of 
the logical consciousness 1 which enriched and deepened our 
logical insight, a debt which Sigwart fully recognizes. In 
the development of this phenomenology two striking charac- 
teristics of the logical consciousness and of its fundamental 
principle, Sufficient Reason, are brought to light. First, 
in that the processes of judgment, of knowledge, are con- 
ceived as a wahres Gesckehen,* a happening in which real and 

1 Logisehe Untersuchungen % Vol. I., p. 135. 
1 Logisehe Untersuchungen % Vol. II., p. 140. 

i ehe Untersuchungen, Vol. [I., p. 17S and p. 312. 



67 

knowledge elements are united, the causal interdependence 
of these processes becomes a fundamental concept. The 
concept of an immanental logical causality of our knowledge 
processes, as the last term of S. R., becomes prominent. And, 
secondly, this ivahres Geschehen, this immanental logic, is 
conceived to be teleological in its nature. This is particu- 
larly marked in Trendelenburg's theory of geometrical 
reasoning. 1 

The necessity which emerges then from this teleological 
movement of the Immanental Logic — is itself not a category 
of merely formal logic — not merely thought necessity in the 
one-sided use of that term, but a necessity both formal and 
material, 2 as the later logicians formulate it, both logical and 
psychological. 

1 Logische Untersuchungen, Vol. II., p. 190, 191. 
3 Logische Untersuchungen, Vol. II., p. 183. 



68 



CHAPTER VI. 

Sufficient Reason as the Basal Principle of 
Modern Logic. 

§79. Before passing to Sigwart we must notice the con- 
tributions of several other men, to the modern logical move- 
ment, but only in so far as they have contributed elements, 
afterward taken up into the modern doctrines of " Sufficient 
Reason," — for we have to do with the historv of modern 
logic only in so far as it affects the fate of our problem. 

1. First of all — Drobisch 1 — between whom and Tren- 
delenburg, in the different editions of their works, a battle 
raged concerning the province of logic, the former always 
maintaining the formal side, according to Herbartian prin- 
ciples. Though logic is formal in its nature, Drobisch also 
maintains that the Law of Ground is the basal principle of 
all logical relations, in striking contrast to the preceding 
formal logic which excluded it as a material principle. Her- 
bart, he says, was the first to recognize the true nature of 
logical ground and consequence, for he showed that ground 
could never be unitary and simple and thus the full nature 
of the relation of ground and consequence exhausted in the 
syllogism. Formal logic is as little satisfied with the syl- 
logism as an expression of grounding as is material thinking. 2 

For the relation between ground and consequence in logic 
is not that which the syllogism at first sight shows: that 
from a simple, already distinct unitary concept a new con- 
cept is deduced. That involves a contradiction, as Herbart 
showed. The ground is equally in formal logic the entire 
interdependence of all the concepts expressed in the syllogism 
upon each other. Thus the relation of ground and con- 
sequence is synthetical and analytical at the same time, 
analytical in so far as subject to the norms of Identity and 
Contractu tion. But being simply the law of the dependence 

1 Logik — ^rd Edition. Introduction. • Logik, — 3rd Edition. §39. 



6 9 

of all concepts upon each other, it excludes the metaphysical 
axiom of causation from consideration as an expression of the 
Law of Ground in the logical sense. 1 The Law of Ground 
is then the fundamental principle of logic to which the prin- 
ciples of Identity and Contradiction are subordinate. It ex- 
presses itself in all relations among ideas, either immediately 
in the logical relations of concepts, or mediately in the 
formal relation of ground and consequence in the syllogism, 
especially in the hypothetical judgment. 

Implied or expressed Sufficient Reason is the basal law 
of all logical relations. 2 

2. Thus is finally reached a clear statement of what Her- 
bart had implied and what Trendelenburg had meant by the 
idea of the co-existence of the conceptual and material ele- 
ments in the ground. That is the concept of an immanental 
logic as over against the clearly expressed formal relations 
of identity, is fully attained. A wider extension of the prin- 
later in Wundt. 

§80. Another principle of importance, not fully attained 
ciple, as well as a more definite formulation is to be found 
in Herbart and Trendelenburg, is finally clearly determined 
by Lotze. The problem of the nature of the causal concept as 
an aspect of the general Law of Ground was throughout the 
history of the principle the most important and yet the most 
difficult to determine. All those who answered it in the meta- 
physical spirit looked upon the causal judgment as synthetic 
and material, without reference to the logical relation of 
ground and consequence. Herbart and Trendelenburg, in 
bringing the whole principle of ground again into the logical 
sphere, are yet not able to determine the proper relation of 
the logical element of ground in the causal concept. 

A distinction between the logical postulate, and the 
empirical elements, both equally present in the causal judg- 
ment in germ, exists, however, as a necessary consequence of 
the consideration of the causal relation as an application of 
the logical postulate of Sufficient Reason. This distinc- 

1 Logik. — 3rd Edition. §39. p. 44. 2 Logik. — 3rd Edition. §57. 



tion is first clearly set forth by Lotze, who goes out from the 
difficulties in the Herbartian doctrine of this relation; for he 
considered that between reals with no quality other than that 
of simple "position," no relation of cause and effect can be 
thought. With Herbart and Trendelenburg he is in accord, 
in the view that the Ratio Sufficiens consists in the whole 
complex of data, and their relations from which the character 
of the supervening effect is deducible and in this sense he 
defines the Aristotelian doctrine of Svvcl/jlls and ivepyela as the 
first expression of Sufficient Reason. But he maintains 
further, that in the Postulate of Sufficient Reason with which 
we come to phenomena we must distinguish between the 
general logical postulate of a necessary relation of ground and 
consequence in the causal concept, and the empirical suffi- 
ciency of a given cause, in bringing about a given effect. This 
distinction, one of the most weighty points of his thinking, is 
treated fully in his metaphysics and logic, but for a concise 
expression, the following quotation from the " Griuidziige der 
Metaphysik" will suffice : — "An die Stelle des falschen Be- 
griffs der schaffenden muss der der wirkenden Ursache 
gesetzt werden. Und dieser richtige Begriff des Causal — 
Nexus enthalt zwei verschmolzene Principien, das der Ratio 
Sufficiens und das der Causa Efficiens." 1 

The latter expresses the logical postulate of necessity, 
the former the empirical sufficiency included in the causal 
concept. Here at last is reached a clear doctrine of the 
relation of Sufficient Reason to causation, from the lack of 
which the whole history ol the problem since Leibnitz had 
suffered. A more complete development of the distinction 
is to be found in Wundt's doctrine which follows in a later 
chapter. 

SIGWART. 

,^.S i . With Sigwart is the place of our Principle in Modern 
Logic definitely secured. Following upon the earlier work of 

Trendelenburg and Uberweg, as he himself remarks in the 

1 Lotze, " GrundtUge der Metaphysik" p. 39. 



7i 

introduction to his Logik, 1 he is enabled to formulate Suffi- 
cient Reason critically, to show its place in logic and its 
relations on the one hand to psychology and on the other to 
metaphysik. i. As a positive result of Trendelenburg's work 
Sufficient Reason receives an important place in his logic 
together with all its unlogical implications, and as a negative 
result of the same work, the line between the psychological 
and metaphysical is closely drawn. As the basal law of logic 
its formulation is as follows: "Jedes Urtheil behauptet 
einen logischen Grund zu haben, der es fur jeden Denkenden 
notwendig macht. . . . Mit dem Grunde ist die Folge 
gesetzt mit der Folge ist der Grund aufgehoben." 2 

This however is a law which, though universal in logic, 
is comparatively limited in its application, for it can apply 
only to judgments whose grounds are known, that is concept- 
ually determined: — "denn streng genommen ein logischer 
grund den wir nicht kennen ist ein Widerspruch, denn er 
wird erst ein logischer Grund dadurch dass wir ihn erkennen." 3 

2. This primal logical law extends then in two directions into 
spheres where the grounds are not all logically, conceptually 
determined — in the form of two postulates, closely connected 
but yet at bottom different, a. The first is the psycholog- 
ical postulate : that no judgment is given without psychological 
ground for its certainty — (iiot necessity), b. The second is the 
causal axiom : that nothing happens in the objective world 
without a sufficient cause. It is important to determine the 
relation of logical Sufficient Reason to these two postulates 
and of each to the other. 

§82. a. Evidently the psychological postulate is much 
more general than the logical for it applies equally to judg- 
ments whose grounds are not known, and to those whose 
grounds are known ; while the logical, strictly speaking, 
governs only the lattter. Subjective certainty, "Geltung's 
Bewustsein," is the most general term for Sufficient Reason, 

1 Cf . Logik, 1873. Introduction. 
* Logik, 1873. §32. 
8 Cf . also Leibnitz, §21. 



72 

in that all logical necessity is also subjectively certain, but 
there is much more subjectively certain that is not logically 
necessary. (Thus the confusion of "Sufficient Reason" 
with psychological necessity as we have seen it exemplified 
in Augustine, Hume, and to an extent in Schopenhauer.) 
But to the phenomenology of this psychological " Geltung's 
Bewustsein " Sigwart denies metaphysical worth — its phen- 
omena must be studied as throwing light upon the logical 
consciousness, by developing the psychological laws with 
which logical judgments are related. In this phenomenology 
of grounding the marks of Trendelenburg are plainly to be 
seen — especially in the chapter on the Modal Categories that 
follows. But into the detail of this movement of grounding 
we cannot enter. While the phenomenology of Grounding 
cannot be taken as of metaphysical value, in Trendelenburg's 
sense, it allows us to postulate back of logical relations of 
ground and consequence, as brought to consciousness in the 
formal judgment, an immanental logic of ideas which encom- 
passes the whole psychological complex which lies back of the 
judgment. So that Sufficient Reason is extended beyond 
formal logic to the place of a general principle of thinking. 
This is well expressed by Beno Erdmann, who, in general, 
repeats the same view as Sigwart, when he says: "Sofern 
das Geltung's Bewustsein aus der Gewissheit und Denknot- 
wendigkeit besteht ist es durch beide bedingt, durch beide 
zureichend begrundet." 1 

§83. b. The second problem is that of the extension of Suffi- 
cient Reason outwardly, as a principle of causal judgments. 
This is expressed in the statement that causation is not a 
peculiar form of Sufficient Reason, but only a postulate of the 
validity of the Principle in an external metaphysical sphere. 
Only in so far, therefore, as a relation of cause and effect 
allows itself to be expressed in the form of a hypothetical 
judgment, can it be said to stand under the logical Law of 
Ground. (Here also Erdmann takes practically the same 

1 J'-rdinann, Logik, #46. 



73 

position, 1 ) Causation is not an independent manifestation of 
Sufficient Reason for the sphere of objective truth, in 
the Schopenhauerian sense, for that includes in it the pre- 
supposition that causation is the Sufficient Reason of exist- 
ence of that objective Reality, which leads to a further meta- 
physical construction of Sufficient Reason in an idealistic 
direction, as the principle which necessitates the objectifica- 
tion of subjective ideas. 2 It is psychologically certain that 
an individual is necessitated to assign his sense affections to 
an outer cause, but it does not follow, that this cause actually 
exists either in space or in thought. Besides, that I am not 
conscious of producing these causal relations does not pre- 
clude the possibility of their being of purely subjective 
origin, therefore does not prove that causation is an objective 
form of "Sufficient Reason." The consequence is that we 
can not consider causality an axiom of reality but only a 
postulate of knowledge. As such a postulate, its relation to 
logical ground and consequence is that of any other a priori 
axiom, in the sense that the existence of this principle or of 
some particular fact based upon it is used as a ground for 
some logical expression of thought. Thus the necessity ex- 
pressed by the hypothetical judgment, which is really the 
only formal expression of the Law of Ground in logic, is 
based upon this axiom which is in every hypothetical judg- 
ment either expressed or implied. 3 In so far as the relation 
of cause and effect is expressed in the hypothetical form of 
judgment, it is taken up into the sphere of the necessity of 
formal logic. 

§ 84. We are now in a position to distinguish between the 
three kinds of grounds developed by Sigwart. There is first, 
— the logical ground in the strict sense of the word in the 
hypothetical relation of two concepts which says that if one 
is true, the other is; if the consequence is proven to be false, 
the ground is false also. Only in this sense is the law of 

1 Erdmann, Logik. $409. 

3 Vol. I. ^48. p. 367. 

5 Sigwart, Logik. Vol. I. p. 211. 



74 

ground an independent law of pure logic, and as such it is 
more of the nature ol a postulate than of a normative law. 
In the second place, that is gound of a judgment which 
psychologically brings it about; therefore the entire complex 
of consciousness out of which a judgment grows. This 
includes partly, merely psychological association of ideas, 
partly conscious comparison according to the logical laws of 
Identity and Contradiction ; partly the a priori postulates, 
especially causation, which is both logical and psychological 
in its necessity. 

The third source of ground is that to which reality is 
attached and which, according to the principle of Sufficient 
Reason, is considered the condition of the existence of another 
element of external reality, called the effect. A considera- 
tion of the mutual relations oi these three grounds to each 
other would show that the only direct logical expression of 
Sufficient Reason is the hypothetical form of judgment, in 
that it stands under the law of ground analytically — the 
consequence is expressly contained in the ground. 1 All other 
forms of judgment are under the law of ground in logical 
imuiancnce. That is, the predicate is contained in the sub- 
ject. This immanence of the predicate in the subject leads 
back, however, to a sphere where the logical necessity is not 
clearly expressed, where the full ground is not known, and 
the grounds thus become partly psychological. Here the 
Law of Ground can only be expressed as a postulate of the 
universality of this logical immanence among our ideas. On 
the other hand, pushing out from the formal relation of 
ground and consequence into external reality we postulate 
the existence of what we merely logically express as ground 
and consequence. In so doing we have fallen back upon the 
causal axiom. 2 Thus equally in both the inner and outer 
direction in consciousness and in what is out of conscious- 
ness, is extended, through postulates, the force of the Law of 
Ground. 

1 Si^wart, " /if it 'rage zur Lehre vom hypotlutischf Urthfile. (Tubingen, 1871). 

1 Erdmann, Logik t pp. 301 and 419. 



75 

WUNDT. 

§ 85 . By far the most important modern statement of Suf- 
ficient Reason is to be found in Professor Wundt's Logik, 
from the second edition of which (1893), the following resum6 
is taken. This is true not only because of the extraordinary 
fulness with which the problem is treated, but equally because 
■ of the definiteness of the place assigned it in logic, and the 
critical acuteness with which the relations of the logical to 
its psychological and metaphysical applications are deter- 
mined. 

It was the failure of Leibnitz, according to Professor 
Wundt, that in his conception of the principle, it was con- 
fined to empirical truth, to the psychological sphere of con- 
fused ideas, thus obscuring at the very beginning of the 
-history the essentially logical nature of the term ground — and 
thus making it identical with the causal axiom, with which 
it has only a distant relation. 1 Kant, despite his severing of 
the Law of Ground from formal logic, fell into a certain 
rationalism, in that identifying the principle with causation, 
he deduces both from the hypothetical judgment. 2 Schop- 
enhauer makes the mistake of putting the weight upon the 
empirical application of the law not upon its original logical 
nature. His method is of the same order as that which 
would seek to make Identity in the intuitiQn and Identity 
in concepts two distinct roots. 3 His fourfold principle with 
its " Intellectuelle Anschauung" must be looked upon as a 
metaphysical rationalism ; nothing more than a remainder of 
the Wolffian logic of reality. Finally any attempt, such as 
that of Hamilton, and later of Riehl, 4 to bring Sufficient 
Reason into logic by subordinating it to the law of Identity 
must fail, for Sufficient Reason expresses just those relations 
in thought which do not come under the rubric of Identity, 
relations of dependence, equivalence, by reason of which the 

1 Wundt, Logik, 2nd Edition, 1693, Vol. I, p. 369. 
5 Wundt, Logik, 2nd Edition, 1893, Vol. I, p. 390. 
8 ( The same), p. 571. 
4 Philosoph. Criticismus, Vol. 2, p. 2jo. 



7 6 

worth of the consequence depends upon the worth of 
the ground. 1 Thus, "if the angles of a right angled 
triangle are equal, so are the sides equal," expresses, in no 
sense, a relation of identity between the ground and the con- 
sequence, but a relation purely of dependence based upon* 
the nature of the reality about which the relation of depend- 
ence is expressed. Besides, if the law were equal to identity,, 
it must read equally "with the consequence is given the 
ground as well as with the ground is given the consequence " 
— a manifest asburdity. 

§86. Thus the Law of Ground is the most general law of all log- 
ical tlwught, a postulate underlying all thinking as " Satz der 
Abhangigkeit unseren Denkacte von einander." 2 As such it 
extends through the entire " Schlusslehre" and is manifested 
in all relations of concepts whether syllogistically expressed 
or not. This formulation striven for by Herbart and ex- 
pressed by Drobisch, 3 is now recognized by Wundt, but 
with the addition that its consequences are further carried 
out. 4 As the general law of the dependence of all logical 
thought, Sufficient Reason is not a normative principle, to 
be applied in carrying out actual judgments. "Denn es 
giebt lediglich dem Postulat, dass der Inhait unsers Denkens 
nach Griinden und Folgen sich ordnen liisse, einen Ausdruck 
und es weist daraufhin dass der Schluss eine solche Ordnung 
herstelle. Aber die Kriterien bleiben unbestimmt. Sehen 
wir uns nun an den einzelnen Beispielen des Schliessens urn, 
so zeigt es sich dass bald Identitat, bald Subsumption den 

'Wundt, Logik, 2nd Edition, i8gj, Vol. I, p. 370. 

3 Vol/,p J73 . 

8 Cf. Par. 79 (above). 

*(This is a step further than Sigwart, who still somewhat under the influence of 
the formal analytical nature of the Law of Ground, confined it formally to the hypo- 
thetical assigning the affirmative- and negative judgments to Identity and Contradiction. 
In the syllogism, the first and second figures were shown to be subject to the principle 
of Suffit lent Reason. For a complete and detailed carrying oul of this principle, that 
the " Abhangigkeit's \ ei haltniss " expressed in Sufficient Reason is the basal law of 
all logical forms — compare the work of Dr. Franz Erhardt, Der Satz vom Crunde als 

Princip dei Schliessens" Halle, [891. 



77 

Orund darstellt." 1 Because of its not being a normative 
law, it will be remembered, Hamilton demands that Sufficient 
Reason be excluded from logic, for as a material principle, 
it coincides with Causation.* On the contrary, it is just 
because it is not a definite normative law, that with Wundt, 
it becomes the basal principle of logic, with the normative 
laws as presuppositions. As such a general law of concepts, 
the Wundtian formulation is as follows: Wenn verschie- 
-denen Urtheile durch Begriffe die Ihnen gemeinsam ange- 
horen in Verhaltniss zu einander gesetzt sind, so stehen 
auch die nicht gemeinsamen Begriffe solchen Urtheilen in 
einem Verhaltniss welches in einem neuen Urtheil seinen 
Ausdruck findet." 3 

Here then is a strictly formal expression of Sufficient 
Reason which fills the demand of Herbart, which was that 
the law of ground be formulated so as to show how new 
judgments can arise. . It is a more precise expression of what 
Herbart meant by widening the concept of the ground, that 
a new consequence might arise. It expresses simply the 
relation of dependence of concepts upon each other, dependent 
not upon the normative laws, but upon the relative worth of 
the concepts for each other. Thus the formula y = ax -\~ b 
stands under the law of ground, for the numerical value of y 
depends upon the numerical value of x. 

§87. But such a general law of ground of the dependence 
of concepts logically upon each other, according to their 
logical worth for each other, in that it is a material principle, 
depends for its value upon its application to experience. To 
what extent then may there be different applications of this 
general law according to the material constitution of the 
ideas which it shall hold in its grasp ? Schopenhauer had 
made the mistake of so putting the weight upon the applica- 
tion, that he developed absolute metaphysical distinctions 
between its four roots, thus reducing the logical form to the 
sphere of a phenomenal application ; for the universal logical 
character, he was thus compelled to substitute an ontological 

*p. 317. *Cf. \ 74 above. 3 Vol. I, p. 317. 



78 

which he called metalogical. 1 In contradiction to this Wundt 
maintains: "Der Satz braucht die Anschauung zu seiner 
Anwendung, aber er ist selbst nicht Gegenstand der An- 
schauung. Daher kann man ihn nicht durch Hinweiss auf 
den Zusammenhang der Erfahrung erkl'aren ; viel mehr ist er es 
erst, durch den unser Denken Zusammenhang hervorbringt." 2 

§88. What then are the particular applications of this 
logical law to phenomena ? They are of two kinds, i. The 
formal in Mathematics. 2. The Material as expressed in 
the different forms of the causal axioms. The more general 
law which governs all its applications is that in order to find 
expression in the data of the "Anschauung," it submits 
itself to the material nature of the " Anschauung," upon 
this depends the extent and validity of the application. 3 

I. The Mathematical Application. Just as this Law of 
Ground is the undeducible a priori axiom of all thought in 
general, so are the special axioms of mathematics the applica- 
tion of the Law of Ground to the concepts of space and time. 
The further application of these axioms to a hypothetical 
substratum of the natural phenomena gives the physical 
axioms. 4 " Alle Mathematische Operationen griinden sich 
also auf Axiome welche Anwendungen des Satzes vom Grunde 
auf mathematische Fundamental-Begriffe darstellen." 5 This 
championing of the logical character of mathematical knowl- 
edge against the Schopenhauerian doctrine of the "An- 
schauung," rests upon Wundt's doctrine of the mathematical 
relations as the most abstract of concepts (which is fully 
developed in the second volume of his Logic, chapter II,. 
when he abandons the Kantian theory of a transcendental 
pure intuition) as so abstract that they are, one might say, 
transparent and therefore allow of an application of the logi- 
cal axioms, more especially of Ground, without anv indeter- 
minable remainder. Schopenhauer's doctrine rests upon a 
false distinction between "Anschauung" and " Begriff " 
growing out of the Kantian doctrine of the pure " Anschau- 

»C£. 851. *Logik x p. 561. 

% Logik, p. 571. % Logik t p. 571- *Logik % p. 577- 



79 

ung." The only difference between the logic of mathemati- 
cal, and non-mathematical concepts, is that in the former the 
" Anschauung " is used in a special symbolical way for the 
proof of the theories; that is empirical constructions are 
called in, in geometry, for the purpose of enabling us to 
deduce particular laws from general axioms, (in the sense ol 
the "Zufallige Ansichten" of Herbart and the teleological 
geometry of Trendelenburg.) But these constructions can be 
said to be a part of the ground only in the particular case 
when they are called in as a means to an end. What really 
stands under the law of ground in the strict sense is the 
deduction according to logical principles. 

§ 89. Over against the complete application of Sufficient 
Reason to Mathematics, its application to experience in the 
Causal Axiom is such that causation fails to fall together 
with the Law of Ground. This failure arises from the fact 
that in the particular empirical causal relation " der Hinweis 
auf das begriindende Denken nicht dargethan ist" — for the 
particular causal relations must be found empirically for 
themselves. The element of the logical Law of Ground 
which is to be found in causation lies in the postulate that 
for every real a sufficient cause must be found. This ration- 
alistic side of causation alone is related to the Law of Ground. 
The arguments of Kant and Schopenhauer both fail to show 
causation to be an a priori principle as source of the par- 
ticular causal judgments. 1 The complete identification of 
causality with Sufficient Reason would only then be allow- 
able "wenn die Ursachen als Pramissen benutzt werden 
konnten aus denen ohne Rucksicht auf bestatigenden Beobac- 
tungen die Wirkungen zu erschliessen waren." 2 Causality, 
then, has a dual nature — "Darum tragt das Causal Gesetz 
den doppelten character eines Gesetzes und eines Postulates 
an sich. Als das Letzte ist causalitat Satz vom Grunde." 3 To 
this extent then can the logical law of ground be said to 
penetrate phenomenal experience — in so far that in conse- 
quence of its postulate, phenomena must be looked upon as 

fc 'Cf. Sigwart, par. 83. 2 p. 610. s Cf. par. 80 (above). 



8o 

under definite laws. "Die unverbriichliche Gesetzmassig- 
keit die das wissenschaftliche Causal Gesetz einschliest, ist 
eine notwendige Folge jener Beziehung zum Satz des Grundes 
die ihm innewohnt." 1 This imperfect relation of the Causal 
Law to the Law of Ground, manifests itself according to the 
material to wmich causality is applied. For we saw that 
Sufficient Reason in general depended upon the Intuition for 
its application, .so here in its application as causality it depends 
upon the nature of the intuition for the character and extent 
of its application, a. "In seiner anwendung auf die Erfah- 
rung richtet sich dieser Grundsatz nach den besonderen 
Bedingungen welche die Erscheinungen unserem, nach Grund 
und Folge verklinftenden Denken entgegen bringen." Fur- 
ther: — b. " Es entspringen so aus ihm die einzelnen Erfah- 
rungs Gesetze die sich sammtlich wieder auf zwei allgemeine 
Principien zuruckfiihren lassen, auf das Causal Gesetz und 
das Zweck Princip." 2 Now the application of the Causal 
Axiom, with its twofold nature, partly the Law of Ground, 
partly that which will not be contained in this primal law of 
logic, results in antinomies which show the extent to which 
the Law of Ground may force itself into phenomena. These 
antinomies are two in number, different according as causa- 
tion is applied to the objective world or to the psychological 
sphere. 

§90. 1. The antinomy of mechanical causation in Natural 
Science. — This antithesis arises between logical causation, or 
causation as the Law of Ground and phenomenal causal 
criteria, from the empirical side. The kernel of the causal 
thought is the idea of determination or more metaphysically 
— of efficiency. 8 But for this efficiency to be conceivable 
naive thought, and ultimately rationalistic reflection, trans- 
lates the Logical necessity over into the sphere of reality by 
demanding that the cause and the effect be in immediate con- 
tact, "so that the force of the cause may pass over into the 
effect." Thus, temporally speaking, the postulate demands 
that cause and effect be simultaneous. This is the nearest 

1 Cf. Lotze's distinction, \ 80 (above). 'Vol. I, p. 574. ■ Cf . Lotze, \ 8o(above.) 



approach to an expression of this logical element in causation. 
On the other hand the study of phenomena shows us that 
invariably the cause and effect appear only as successive. 
Thus in an early edition of his Logik 1 we find the antinomy 
formulated as follows: 



Thesis: 
(Rational) 
Ursache und Wirkung sind 
zugleich. 

equally 
Mit dem Aufhoren der Ur- 
sache erlischt die Wirkung. 



Antithesis: 
(Empirical) 
Die Ursache geht der Wirk- 
ung voran. 

also 
Nach dem Aufhoren der Ur- 
sache verharrt die Wirkung. 



This antinomy shows how far the Law of Ground pene- 
trates reality as the causal axiom. In its pure logical form 
it cannot enter but is met by a refusal on the part of 
phenomena to conform to its demands. In the modified form 
of a partly empirical law it can attain "sufficiency" — that is 
sufficient causes may be found, but the absolute determin- 
ation of the logical postulate, reality resists. Such a deter- 
mination is only possible on the basis of a metaphysical theory 
of the phenomenal causal relations being transparent con- 
cepts for the application of the logical Principle of Ground 
— the postulate of a logic of the Universe. So long as we 
abstain from a metaphysic, these antinomies do not trouble 
us. 

§91. But still more complicated becomes the antinomy 
when the Law of Ground is applied to the sphere of psycho- 
logical phenomena. Here it is the antithesis between caus- 
ality "als Erzeugniss unseres Denkens und unser Denken als 
Erzeugniss der natur." Here we have turned the Law of 
Ground upon the phenomena of consciousness, and as upon 
any other phenomena, here also it makes the demand that 
the relation of the phenomena of consciousness, of the ideas 
which make it up be logically necessary. Now if we look at 
the ideal content of consciousness, from one side, it will be 

x Logik, i88o-'83, p. 536. 



82 

seen that from the standpoint of the theory of knowledge 
these ideas in their relations, concept to concept, stand 
under this general logical law of Sufficient Reason or of the 
dependence of concepts upon each other, for it was in this 
sphere that we saw the law in its original form expressed. 
Here it will be seen, we have gone out from the results of 
the activity of consciousness. But if on the contrary we 
look upon psychological life, in its entirety aside from its 
value for knowledge, the application of the Law of Ground 
must be two-fold, of the nature of an antinomy as in the case 
of the application to external reality. For on the one hand 
the mere association of ideas, by reason of its connection 
with the external world, is subject to mechanical causation; 
to will acts however must be assigned an inner causality, for 
they are governed by the teleological principles of purpose 
and worth. How then does the general logical principle of 
Sufficient Reason relate to these two different sides of the 
content of consciousness? Of course, in so far as the assoc- 
iation of ideas is governed by mechanical laws, the Law of 
Ground is applied according to the principle expressed in 
the preceding paragraph, but on the other hand the relation 
between the logical Law of Ground and the inner teleolog- 
ical causality is of another sort. For this problem Wundt 
has a simple, and yet far reaching answer. The primal 
Law of Ground and the inner causality are identified. In 
other words the inner causality as represented in the higher 
apperceptive processes of judgment and will is an immediate 
manifestation of the primal Law of Ground. "Fur die 
Wirkung innerer Kraft giebt nicht eine gewaltige Umform- 
ung der natur-causalitat, wie in Psycho-physik, sondern 
hier greift die logiscJie Causalitdt in Hirer urspriinglicJien Gestalt 
Platz, der Satz vom Grunde selbst." ' 

With this striking cutting of the Gordian-Knot, two of 
the most difficult problems of the whole history of the Prin- 
ciple of Sufficient Reason seem to be solved, a. The first 
problem of the relation of the logical Law of Ground to the 

1 I.ogik, Vol. I, p. 627. 



83 

Causality of the will, which was variously solved, either by 
making the latter independent of the logical laws as in 
Crusius, or identifying it with mechanical causation as in 
Schopenhauer, is now solved by so extending the logical 
Law of Ground as to include the logical causality of con- 
sciousness which works under the laws of " ends and worths." 1 
b. The second, more especially epistemological, problem 
concerns the relation of this primal logical law and its neces- 
sity to the " sufficiency" of the psychological processes which 
produce the logical results. Here again the concept of logi- 
cal causality is extended to include all these psychological 
processes out of which the logical "resultants" arise. Here 
again " der Satz vom Grunde greift in ihrer urspriinglichen 
Gestalt Platz." Logical necessity lies alone in the " Resul- 
tanten" of these apperceptive processes, 2 but in that these 
results act as the immanental ends of the processes that 
precede them, is the whole movement under logical causal- 
ity, or in other words the whole apperceptive side of con- 
sciousness is under the Law of Ground. The relations of 
cause and effect between " resultant " and the process which 
has brought it about, are decided not by equivalence of forces 
as in mechanical causation, but by equivalence of values 3 
between the process which is considered ground and the 
judgment which results. 

§92. This doctrine of Logical Causality as governing the 
whole apperceptive side of consciousness, brings the element 
of teleology in the Law of Ground, again strikingly to the 
front. The Law of Ground as applied to consciousness and its 
content (except in so far as that content is under association 
laws) must be applied as a teleological principle, for the 
Sufficient Reason that in applying the Law of Ground to 
conscious content we go backward from the "resultants" to 
the sources, and these "resultants" are judged alone by 

1 ' ' Zwecke und Werthe. " 

2 Logik, Vol. I, p. 81. Cf. also the Psychological Law of " Resultanten " — 
*' Grundriss der Psychologie" (1896), $ 23. 
3 Logik, Vol. I, p. 612. Note. 



8 4 

their purpose or value for consciousness, exactly the opposite 
of the application to mechanical causation. " Zweck und 
Causalitat springen aus verschiedenen Betrachtungsweisen 
derselben Vorgange " — und " seit die Causalitat von dem 
Grunde zu Folge fortschreitet, der zweck aber von der 
Folge zum Grunde zurlick, so sind beide die einzeln mogliche 
Gestaltungen des Satzes vom Grunde." 1 The important 
point however is, that, although not shut out from the sphere 
of causal observation of nature, teleology yet finds the chief 
application as a principle of grounding in the sphere of con- 
scious processes, either judgments or will acts. One need 
only compare this treatment of the teleological element with 
that of Leibnitz to see the full meaning of the development. 
With Leibnitz teleology is identified with causation, as the 
Law of Ground ruling outside of logic ; here it is the Law of 
Ground ruling as logical causality in our conscious apper- 
ceptive processes. 

§93. To the final metaphysical question whether there is 
any common term for the solution of this antinomy between 
the two sides of the Law of Ground, the mechanical causa- 
tion and logical causality as they stand over against each 
other in the sphere of conscious processes, Wundt answers 
with the hypothesis of a transcendental thinking Will, mani- 
fested in this logical causality or apperception, 2 but as far as 
the empirical problem is concerned there remains a perma- 
nent antinomy of attitude, for to give one or the other a 
ruling place, is to attempt the solution of a metaphysical 
problem with empirical means. 3 

1 Logik, Vol. I, p. 612. Note. a Logik, Vol. I. p. 630. *Logik, Vol. I, p. 628. 



85 



CONCLUSION. 

§99. This resume of Wundt's doctrine of Sufficient 
Reason shows the main weight to lie upon its definition as 
the basal principle of logic; and then, secondly, in the 
critical determination of the extent and nature of its applica- 
cation to phenomena — 1) to external phenomena in the causal 
axiom, and 2) to the actuality of the processes of conscious- 
ness ; in other words, to the metaphysical and psychological 
problems. Here then is a concise and critical determination 
of the mutual relation of the three elements most prominent 
in the history of the law. These critical results must be 
compared with the points of view attained at the different 
stages of the development of the principle, if the importance 
of its outcome for modern thought is to be appreciated. 
Such a comparison, in brief, the introductory chapter 
aimed to facilitate. And the succeeding detailed treatment 
of the struggle between the metaphysical and logical motives, 
out of which the first formulation of Sufficient Reason 
arose, and of the final victory of the logical standpoint has, it 
is to be hoped, only served to impress upon the reader the 
inherent necessity of the movement. 

The concomitant development of what has been called 
the modern logical consciousness and the corresponding dis- 
integration, or at least loss of importance of the metaphysi- 
cal motive, it has been constantly maintained, lies deeply 
rooted in the necessity of this movement. Only, in such 
light, is it possible to understand the meaning of the develop- 
ment of this fundamental postulate from an extra-logical to 
a fundamentally logical formulation, according to which it is 
first of all a logical postulate, with only secondary applica- 
tions to the metaphysical real. This logical consciousness 
knows no higher law than the postulate that empirical 
knowledge is alone possible by means of conceptual logical 
relations, although the bonds of the logical consciousness 
have been extended. 



86 

The satisfaction of the desire for unification can go no 
further than the postulate that all phenomena which come to 
our knowledge must be under the universal principles of 
logic in order to be known. Whether these principles ex- 
haust the nature of the reality of these phenomena is another 
question. Thus Dilthey, in closing the first volume of the 
Einleitiing in die Geistes Wissenschaften, which is concerned 
with the history of the disintegration of metaphysics and the 
rise of the modern mental sciences, calls attention to the fact 
that, by looking backward, we may see that the attempt at a 
unitary metaphysical formulation of Sufficient Reason has 
been the problem of the whole modern metaphysical move- 
ment. The failure to accomplish it has been the failure of 
metaphysics in general. 1 This, then, is the meaning of the 
giving up of a metaphysical for a merely logical theory of 
Sufficient Reason. Only so far as the ground is logically 
conceived is it necessary. As material principle it can only 
be "sufficient" not metaphysically determining, as Crusius 
and Kant would have. The only possible way of grasping 
reality, then, is by seeking relations of logical thought neces- 
sity in the relativity of experience. Into this relativity 
Science, whose ideal is a contradictionless whole of experi- 
ence, brings logical method, constitutes an objective sphere 
of space, time and causality. The mathematics of space and 
time; the various sciences, mental and physical, with their 
various causalities, reducible, however, to physical and 
psychical, constitute the limits of the function of the 
postulate of Sufficient Reasofckas applied to phenomenal real- 
ity. But the element of necessity, common to all these 
forms, is just the logical postulate which forms the skeleton 
of thought. Those elements, which are peculiar to the par- 
ticular applications of the postulate to definite particular 
material, are only of the nature of subjective sufficiency, and 
not determining necessity. This is evidently the opposite, 
in every particular, of Schopenhauer's position, which 

1 Dilthey, " Bin UitUHg in <lir Geistes WissenscJiaftcn" p. 407-5 19. 



87 

ascribes to them, not to the logical kernel, the source of 
necessity. 

With the limits of the validity of this logical postulate in 
trans-phenomenal usage, this paper has, of course, nothing to 
do. There may be a logic of reality, which is independent 
of the laws of empirical knowledge, but in so faf as the Law 
of Ground is concerned with phenomena, we are constrained 
to say, from the results of the foregoing study, that the ex- 
tension of the postulate is limited, by the very nature of the 
material to which it is applied, to the surface of things. The 
postulate of a contradictionless whole of experience, which 
since Herbart has been a characteristic definition of Suf- 
ficient Reason, cannot be pressed so far as to lead us to seek 
the real beyond experience, but can only be extended as far 
as the logical element in the experiential laws demands. 

The impulse to metaphysical unification, often falsely 
identified with the technical Law of Ground, though it 
demands rightly a fundamental place in thought must in so 
far be subordinated to the critically determined limits of the 
material applications of Sufficient Reason, that in the 
interests of unity, distinctions so vital, as for instance that 
between physical and psychical causality, are not obscured. 
This critical standpoint reflection has attained by a long 
process of struggle, which it has been the aim of the preced- 
ing pages to portray ; and such a standpoint is not likely to 
be lost. It has been a struggle simply because, in attaining 
a standpoint from which the bold logical nature of this pos- 
tulate is clearly seen, of necessity, the more subjective postu- 
lates, ethical and religious, as well as the metaphysical 
demand for unity, have been forced one by one to fall away. 
Historically, even until Leibnitz's time, through the Greeks, 
Augustine, Descartes and Spinoza, Sufficient Reason had 
religious or ethical coloring, as well as metaphysical. The 
Leibnitzians, the Kantians, and even the Herbartians, failed to 
separate it entirely from metaphysical demands, and to give 
it a purely logical self-sufficiency. This the modern logical 
consciousness, which is only another aspect of what is called 



the modern scientific consciousness, has partially attained. 
A certain formalism and abstraction cannot be denied to the 
process, and the religious, ontological postulates remain just 
as strong though separated by the development of our 
thought from the logical Law of Ground. Perhaps all these 
worth categories might be found to have a "sufficiency" 
of their own, and the abstraction by means of which we come 
to a critical understanding of the logical Law of Ground, 
may only serve to bring the antithesis more plainly to our 
consciousness. At all events the critical results cannot be 
undone. 



THE END. 



LIBRARY OF CONGRESS 



029 779 803 



VITA. 



The writer of this dissertation, Wilbur Marshall Urban, 
was born March 27, 1873, in the city of Philadelphia, in the 
State of Pennsylvania, the first son of the Reverend Abram 
Urban, a clergyman in the Protestant Episcopal Church, 
and was baptized and confirmed in the same confession. 
Having received the elements of education in the public 
schools of his native city, and being prepared for the univer- 
sity in the William Penn Charter School of Philadelphia, he 
was admitted to Princeton University in the fall of 1891. 
After two years of study of the Humanities, and two years 
entirely devoted to Philosophy, he was graduated in 1895 
with the Baccalaureate degree and was appointed James 
McCosh Fellow in Mental Science. Immediately upon grad- 
uation, the author visited Germany, spending the first two 
semesters in Jena, where he availed himself of the opportu- 
nity to hear the lectures of Professors Euchen, Liebmann, 
Ziehen and Dr. Erhardt. The winter semester of 1897 was 
spent in Leipzig under the teaching of Professors Heinze, 
Wundt, Volkelt and Schmarsow, after which the examination 
for the degree of Doctor of Philosophy was successfully 
passed. The author desires to express to his honored teach- 
ers his deep appreciation of their helpful interest. 



